+publisher:"Colorado State University" +contributor:("Marchese, Anthony")

Colorado State University

1. Babazadeh, Iman Andrew. Development of a Martian in-situ hybrid rocket motor.

Degree: MS(M.S.), Mechanical Engineering, 2020, Colorado State University

URL: http://hdl.handle.net/10217/212043

► One of the chief obstacles that has prevented a human mission to Mars is the excessive amount of mass that must be launched into low… (more)

▼ One of the chief obstacles that has prevented a human mission to Mars is the excessive amount of mass that must be launched into low earth orbit to assemble the Mars-bound spacecraft. Since propellants alone account for 75% of the total mass requirements, a new concept has been proposed for both manned missions and unmanned robotic sample return missions, which relies on In-Situ Resource Utilization wherein propellants for the return trip to Earth are manufactured from raw materials available on Mars. This research focused on the development and testing of a unique propulsion system that could enable in-situ use of the Martian atmosphere as an oxidizer source and Martian soil as a fuel source for the return journey back to Earth for manned and unmanned vehicles. The propulsion system employs carbon dioxide as an oxidizer and metals as the fuel component. The need to understand and test this concept is significant as there is currently little experimental knowledge on the performance of carbon dioxide oxidizer and metallic fuels in rocket engines. Aluminum and magnesium fuels are the leading choice for burning with carbon dioxide as they can liberate the contained oxygen for rapid combustion to occur. Magnesium is favorable for its ignitability characteristics, whereas aluminum has a higher energy density but is more difficult to ignite due to the formation of its oxide layer. In the research conducted for this thesis, aluminum and magnesium particles were both considered to determine an optimal system that could be used to model an actual Mars propulsion system. The project entailed a myriad of combustion tests based on a conventional hybrid rocket motor in which the metallic fuel particles were encased in a polymer matrix binder and oxidized through a liquid oxidizer. The hybrid rocket motor configuration is not only amenable for the Mars environment because of ease of storage, but also afforded great adaptability safety for the experimental studies described here because of the simplicity of refueling procedures and because the fuel component itself aids in keeping the combustion chamber wall cool, thereby eliminating the need for an active cooling system. Through initial testing, it was observed that adding an additional oxidizer aided in the combustion of carbon dioxide with high percentage metal fuel grains. Specifically, the results of this study suggest that using nitrous oxide as a complementary oxidizer was beneficial in attaining sustained combustion. However, it was also found that miscibility and mixing issues between the carbon dioxide and nitrous oxide oxidizers led to induced combustion instability during the hybrid test fires that had a 50% carbon dioxide and 50% nitrous oxide mixture ratio. Advisors/Committee Members: Marchese, Anthony (advisor), Mizia, John (advisor), Bareither, Christopher (committee member).

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APA (6^th Edition):

Babazadeh, I. A. (2020). Development of a Martian in-situ hybrid rocket motor. (Masters Thesis). Colorado State University. Retrieved from http://hdl.handle.net/10217/212043

Chicago Manual of Style (16^th Edition):

Babazadeh, Iman Andrew. “Development of a Martian in-situ hybrid rocket motor.” 2020. Masters Thesis, Colorado State University. Accessed March 05, 2021. http://hdl.handle.net/10217/212043.

MLA Handbook (7^th Edition):

Babazadeh, Iman Andrew. “Development of a Martian in-situ hybrid rocket motor.” 2020. Web. 05 Mar 2021.

Vancouver:

Babazadeh IA. Development of a Martian in-situ hybrid rocket motor. [Internet] [Masters thesis]. Colorado State University; 2020. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10217/212043.

Council of Science Editors:

Babazadeh IA. Development of a Martian in-situ hybrid rocket motor. [Masters Thesis]. Colorado State University; 2020. Available from: http://hdl.handle.net/10217/212043

Colorado State University

2. Falloon, Thomas. Effect of fuel additives in a natural gas and gasoline engine, The.

Degree: MS(M.S.), Mechanical Engineering, 2016, Colorado State University

URL: http://hdl.handle.net/10217/178951

► Fuel additives are used worldwide for a variety of applications including increasing fuel efficiency, decreasing emissions, decreasing knock propensity and/or modifying storage/handling properties. Because of… (more)

▼ Fuel additives are used worldwide for a variety of applications including increasing fuel efficiency, decreasing emissions, decreasing knock propensity and/or modifying storage/handling properties. Because of the high percentage of global fossil fuel consumption attributed to internal combustion engines, fuel additives that increase the efficiency of fossil fuel powered internal combustion engines can greatly impact global fossil fuel consumption and greenhouse gas emissions. In this study, the effect of various fuel additives on spark ignited natural gas and gasoline internal combustion engines was examined. The natural gas work focused primarily on using fuel additives to extend the lean limit, while the gasoline additives work focused on lean limit extension, decreased knock propensity and increased power. Experiments were performed in using a constant speed, single cylinder, variable compression ratio Cooperative Fuel Research (CFR) engine, which has the capability to operate with both gaseous and liquid fuels. The gaseous fuel system used compressed air to simulate a turbocharged engine, while the liquid fuel system used a naturally aspirated carburetor. In-cylinder pressure data were acquired using a high-speed piezoelectric pressure transducer, which is used to calculate indicated power, peak pressure and to quantify engine knock. In this study, four natural gas and three gasoline additives were considered. For the natural gas fuel additives, the primary hypothesis for the fuel additives was that the lean limit would be decreased with the addition of the additives. By holding the power of the engine constant and decreasing the equivalence ratio, this hypothesis was tested and it was concluded that the additives had a negative impact on the lean limit. For the gasoline additives, the hypothesis was that the additives would either increase engine power, decrease the knock propensity (i.e. increase the octane number), or decrease the lean limit. It was found that one of the additives increased engine efficiency slightly and decreased the knock propensity, while the other two gasoline additives had negative impacts on both metrics. One of the gasoline additives appeared to slightly extend the lean limit, but further testing will be required to confirm this result. Advisors/Committee Members: Marchese, Anthony (advisor), Olsen, Daniel (advisor), Reardon, Kenneth (committee member).

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APA (6^th Edition):

Falloon, T. (2016). Effect of fuel additives in a natural gas and gasoline engine, The. (Masters Thesis). Colorado State University. Retrieved from http://hdl.handle.net/10217/178951

Chicago Manual of Style (16^th Edition):

Falloon, Thomas. “Effect of fuel additives in a natural gas and gasoline engine, The.” 2016. Masters Thesis, Colorado State University. Accessed March 05, 2021. http://hdl.handle.net/10217/178951.

MLA Handbook (7^th Edition):

Falloon, Thomas. “Effect of fuel additives in a natural gas and gasoline engine, The.” 2016. Web. 05 Mar 2021.

Vancouver:

Falloon T. Effect of fuel additives in a natural gas and gasoline engine, The. [Internet] [Masters thesis]. Colorado State University; 2016. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10217/178951.

Council of Science Editors:

Falloon T. Effect of fuel additives in a natural gas and gasoline engine, The. [Masters Thesis]. Colorado State University; 2016. Available from: http://hdl.handle.net/10217/178951

Colorado State University

3. Sutley, Frank H. Installation and testing of a Cummins QSK19 lean burn natural gas engine.

Degree: MS(M.S.), Mechanical Engineering, 2013, Colorado State University

URL: http://hdl.handle.net/10217/79191

► The goal for a more efficient engine will never disappear. Over the years many different techniques have been explored within the common goal of higher… (more)

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APA (6^th Edition):

Sutley, F. H. (2013). Installation and testing of a Cummins QSK19 lean burn natural gas engine. (Masters Thesis). Colorado State University. Retrieved from http://hdl.handle.net/10217/79191

Chicago Manual of Style (16^th Edition):

Sutley, Frank H. “Installation and testing of a Cummins QSK19 lean burn natural gas engine.” 2013. Masters Thesis, Colorado State University. Accessed March 05, 2021. http://hdl.handle.net/10217/79191.

MLA Handbook (7^th Edition):

Sutley, Frank H. “Installation and testing of a Cummins QSK19 lean burn natural gas engine.” 2013. Web. 05 Mar 2021.

Vancouver:

Sutley FH. Installation and testing of a Cummins QSK19 lean burn natural gas engine. [Internet] [Masters thesis]. Colorado State University; 2013. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10217/79191.

Council of Science Editors:

Sutley FH. Installation and testing of a Cummins QSK19 lean burn natural gas engine. [Masters Thesis]. Colorado State University; 2013. Available from: http://hdl.handle.net/10217/79191

Colorado State University

4. Gattoni, John. Advanced control techniques and sensors for gas engines with NSCR.

Degree: MS(M.S.), Mechanical Engineering, 2012, Colorado State University

URL: http://hdl.handle.net/10217/67560

► High exhaust emissions reduction efficiency from an Internal Combustion Engine (ICE) utilizing a Non Selective Catalyst Reduction (NSCR) catalyst system requires complex fuel control strategies.… (more)

▼ High exhaust emissions reduction efficiency from an Internal Combustion Engine (ICE) utilizing a Non Selective Catalyst Reduction (NSCR) catalyst system requires complex fuel control strategies. The allowable equivalence ratio operating range is very narrow where NSCR systems achieve simultaneous reduction of Carbon Monoxide (CO), Nitrogen Oxides (NOx), Total Hydrocarbons (THC), Volatile Organic Compounds (VOC's), and formaldehyde (CH2O). This range is difficult to maintain as transients are introduced into the system. Current fuel control technologies utilizing lambda sensor feedback are reported to be unable to sustain these demands for extended operation periods. Lambda sensor accuracy is the critical issue with current fuel controllers. The goal of this project was to develop a minimization control algorithm utilizing a Continental NOx sensor installed downstream of the NSCR catalyst system for feedback air/fuel ratio control. When the engine is operated under lean conditions, NOx is produced in the engine out exhaust emissions and the NOx sensor responds accordingly. When the engine is operated under rich burn conditions, the NSCR catalyst system produces Ammonia (NH3). NOx sensors have a cross sensitivity to NH3 and will respond as though it has been exposed to NOx. This behavior provides a unique control strategy that allows lambda sensor calibration to be ignored. Testing was performed on a Cummins-Onan Generator Set, model GGHD 60HZ, capable of a power output of 100kW at standard ambient air conditions. The engine was reconfigured to operate utilizing an electronic gas carburetor (EGC2) with lambda sensor feedback, manufactured by Continental Controls Corporation (CCC) and a high reduction efficiency NSCR catalyst system manufactured by DCL International. A Data Acquisition (DAQ) system manufactured by National Instruments (NI) acquired the NOx sensor output. The control algorithm was programmed utilizing a LabVIEW interface and a feed forward command was executed through the NI DAQ system to the CCC EGC2 where the fuel trim adjustment was physically made. Exhaust gas species measurements were acquired via a Rosemount 5-gas analyzer and a Nicolet 6700 FTIR. Fuel composition was acquired utilizing a Varian CP-4900 Micro GC and Air Fuel Ratio (AFR) was obtained with an ECM AFRecorder 4800R. Results utilizing NOx sensor feedback control revealed that under steady state operating conditions, improvements in emissions reduction efficiency of CO, NOx, and THC were significant. The system was also evaluated during load and fuel composition transients. Advisors/Committee Members: Olsen, Daniel (advisor), Marchese, Anthony (committee member), Young, Peter (committee member).

Subjects/Keywords: NSCR; fuel control; NOx sensor; natural gas engines; catalyst; control algorithm

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APA (6^th Edition):

Gattoni, J. (2012). Advanced control techniques and sensors for gas engines with NSCR. (Masters Thesis). Colorado State University. Retrieved from http://hdl.handle.net/10217/67560

Chicago Manual of Style (16^th Edition):

Gattoni, John. “Advanced control techniques and sensors for gas engines with NSCR.” 2012. Masters Thesis, Colorado State University. Accessed March 05, 2021. http://hdl.handle.net/10217/67560.

MLA Handbook (7^th Edition):

Gattoni, John. “Advanced control techniques and sensors for gas engines with NSCR.” 2012. Web. 05 Mar 2021.

Vancouver:

Gattoni J. Advanced control techniques and sensors for gas engines with NSCR. [Internet] [Masters thesis]. Colorado State University; 2012. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10217/67560.

Council of Science Editors:

Gattoni J. Advanced control techniques and sensors for gas engines with NSCR. [Masters Thesis]. Colorado State University; 2012. Available from: http://hdl.handle.net/10217/67560

Colorado State University

5. O'Connell, Matthew. Statistical analysis of the challenges to high penetration of wind energy.

Degree: MS(M.S.), Mechanical Engineering, 2014, Colorado State University

URL: http://hdl.handle.net/10217/84046

► Grid penetration of renewable energy technologies, especially wind power, is higher than ever and continues to increase. The inherent stochastic variability of wind makes predicting… (more)

▼ Grid penetration of renewable energy technologies, especially wind power, is higher than ever and continues to increase. The inherent stochastic variability of wind makes predicting wind, and thus power generation difficult. Generating companies usually don't openly share power output predictions or historical generation data which increases the level of complexity when determining new wind plant locations or estimating delivered grid level power. This work focuses on statistical data analysis and advanced data modeling related to wind power forecasting and generation. The first part of this thesis uses power output logs from several wind plants and a well-known forecasting method to determine energy storage requirements for individual wind plant contract firming. Forecasts of varying accuracy are used to characterize storage requirements based on contract period length, forecast lead time, and forecast accuracy. Results show that forecast error distributions are effected more by forecast accuracy and lead time than wind plant size and location. The biggest reductions in produced power deviations can be achieved by increasing forecast accuracy and decreasing forecast lead time. The second part of this work develops a statistical analysis which allows estimation of contract firming requirements for a specific wind plant location without the need for time series wind and forecast data. The developed method requires only a wind speed and forecasting error distribution. Using these distributions, deviations between forecast to produced power and energy can be estimated. Results from comparing to historical time series data show this method is accurate to within 10% of actual amounts. Since distributions are much more easily attained than historical time series data, this analysis is useful for developers when evaluating potential new locations. The third part of this work uses a pattern matching algorithm to recognize wind ramp events and separate the forecasting error due to timing from the forecasting error due to magnitude. Wind ramp detection is achieved by developing a pattern matching algorithm which is also shown to work in identifying start and stop transients in electrical device current draw. The analysis confirms wind ramp events can be detected by calculating a bimodal ranking value from a histogram of power data, and the effects of forecast timing and magnitude can be separated from overall forecasting errors. The results of this analysis show magnitude errors contribute more in large wind ramp events, while timing errors contribute more in small ramp events. Advisors/Committee Members: Marchese, Anthony (advisor), Zimmerle, Daniel (advisor), Young, Peter (committee member).

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APA (6^th Edition):

O'Connell, M. (2014). Statistical analysis of the challenges to high penetration of wind energy. (Masters Thesis). Colorado State University. Retrieved from http://hdl.handle.net/10217/84046

Chicago Manual of Style (16^th Edition):

O'Connell, Matthew. “Statistical analysis of the challenges to high penetration of wind energy.” 2014. Masters Thesis, Colorado State University. Accessed March 05, 2021. http://hdl.handle.net/10217/84046.

MLA Handbook (7^th Edition):

O'Connell, Matthew. “Statistical analysis of the challenges to high penetration of wind energy.” 2014. Web. 05 Mar 2021.

Vancouver:

O'Connell M. Statistical analysis of the challenges to high penetration of wind energy. [Internet] [Masters thesis]. Colorado State University; 2014. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10217/84046.

Council of Science Editors:

O'Connell M. Statistical analysis of the challenges to high penetration of wind energy. [Masters Thesis]. Colorado State University; 2014. Available from: http://hdl.handle.net/10217/84046

Colorado State University

6. Wilvert, Hurley Nicholas. Development and testing of a solid core fiber optic delivery system and ultraviolet preionization for laser ignition.

Degree: MS(M.S.), Mechanical Engineering, 2012, Colorado State University

URL: http://hdl.handle.net/10217/68142

► Laser ignition of natural gas engines has shown potential to improve many facets of engine performance including brake thermal efficiency, exhaust emissions, and durability as… (more)

▼ Laser ignition of natural gas engines has shown potential to improve many facets of engine performance including brake thermal efficiency, exhaust emissions, and durability as compared with traditional spark ignition. Laser ignition technology has yet to transition to industry primarily because no system for reliably and safely delivering the laser pulse to the combustion chamber exists. This thesis presents a novel fiber optic delivery approach using solid core multimode step index silica fibers with large cladding diameters (400 μm core, 720 μm cladding). Testing was done on the fibers to determine their response to bending, vibration, high power input, and long duration beam transmission. It was found that in configurations representative of what is required on a real engine, and in the presence of vibration, reliable spark formation could be achieved in pressures as low as 3.4 bar using a specially designed optical spark plug. Comparative tests between the fiber delivered laser ignition system and a traditional J-gap spark plug were performed on a single cylinder Waukesha Cooperative Fuel Research (CFR) engine running on bottled methane. Tests were run at three different Net Mean Effective Pressures (NMEP) of 6, 8, and 12 bar at various air-fuel ratios. Results indicate reliable performance of the fiber and improved engine performance at high NMEP and lean conditions. Thesis research also includes initial studies into the use of dual laser pulses for plasma formation and ignition. In this approach, a first ultraviolet pulse preionizes a volume of air while a second overlapped pulse adds additional energy. Electron density measurements reveal the ultraviolet beam generates substantial preionization even with no visual breakdown, and Schlieren images are used to study the interaction between the two beams at atmospheric and lower pressures. Advisors/Committee Members: Yalin, Azer (advisor), Marchese, Anthony (committee member), Rocca, Jorge (committee member).

Subjects/Keywords: fiber optic; laser ignition

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APA (6^th Edition):

Wilvert, H. N. (2012). Development and testing of a solid core fiber optic delivery system and ultraviolet preionization for laser ignition. (Masters Thesis). Colorado State University. Retrieved from http://hdl.handle.net/10217/68142

Chicago Manual of Style (16^th Edition):

Wilvert, Hurley Nicholas. “Development and testing of a solid core fiber optic delivery system and ultraviolet preionization for laser ignition.” 2012. Masters Thesis, Colorado State University. Accessed March 05, 2021. http://hdl.handle.net/10217/68142.

MLA Handbook (7^th Edition):

Wilvert, Hurley Nicholas. “Development and testing of a solid core fiber optic delivery system and ultraviolet preionization for laser ignition.” 2012. Web. 05 Mar 2021.

Vancouver:

Wilvert HN. Development and testing of a solid core fiber optic delivery system and ultraviolet preionization for laser ignition. [Internet] [Masters thesis]. Colorado State University; 2012. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10217/68142.

Council of Science Editors:

Wilvert HN. Development and testing of a solid core fiber optic delivery system and ultraviolet preionization for laser ignition. [Masters Thesis]. Colorado State University; 2012. Available from: http://hdl.handle.net/10217/68142

Colorado State University

7. Butte, Carter Vincent. Investigation of dual-pulse laser plasmas for ignition of fuel-air mixtures.

Degree: MS(M.S.), Mechanical Engineering, 2020, Colorado State University

URL: http://hdl.handle.net/10217/208417

► Progress towards more complex combustion applications has demanded more advanced and versatile ignition techniques. One attempt to address some of the concerns associated with well-established… (more)

▼ Progress towards more complex combustion applications has demanded more advanced and versatile ignition techniques. One attempt to address some of the concerns associated with well-established techniques such as spark plugs and igniters is laser plasma ignition. Advantages of laser ignition include flexibility of spark location and timing, reduced NOx formation, leaner engine operation, increased combustion efficiency, and greater system longevity at elevated pressures. Additionally, the non-intrusive nature of laser plasmas results in more unperturbed kernel evolution, as mounting hardware is not required. This is an advantage when compared with spark plug or igniter electrodes which typically act as heat sinks quenching the flame. However, large input energies, complications with beam delivery, and undesirable kernel dynamics have impeded field implementation. Our approach to address these challenges uses a dual-pulse laser plasma where an ultraviolet (UV) beam preionizes a gas mixture and a second near infrared (NIR) beam increases the energy and ionization state of the gas. The use of this technique decouples the processes responsible for ionization, predominantly multiphoton ionization (MPI) and electron avalanche ionization (EAI) through inverse bremsstrahlung absorption, and allows for tailoring of plasma properties through adjustments to beam energies and delay time. Recent work has shown that dual-pulse laser plasmas not only reduce energy requirements but also enhance ignition characteristics such as combustion efficiency, particularly around the lean limit.6 The present thesis serves to fill voids in the existing literature with regards to plasma properties and ignition characteristics in various fuels, as well as present a new resonant preionization scheme targeting molecular oxygen at λ=287.5 nm. Four laser plasmas are investigated in this work: non-resonant single pulse (λ=1064 nm), non-resonant dual-pulse (preionization at λUV=266 nm with energy-addition at λNIR=1064 nm), resonant single-pulse (λREMPI=287.5 nm), and resonant dual-pulse plasma (preionization at λREMPI=287.5 nm and energy addition at λNIR=1064 nm). Each of these plasmas are analyzed for electron density and gas temperature using combined Rayleigh Thomson scattering, and are studied for ignition of propane-air, methane-air, and hydrogen-air mixtures. In the analysis, these experimental results are combined with past results to give a comprehensive picture of the ignition abilities of single pulse and dual-pulse plasmas in propane-air, methane-air, and hydrogen-air mixtures. Together, knowledge of plasma properties and ignition characteristics give us a more complete picture of the capabilities and limitations of each plasma for combustion applications. Advisors/Committee Members: Yalin, Azer (advisor), Marchese, Anthony (committee member), Bailey, Ryan (committee member).

Subjects/Keywords: dual-pulse; combustion; plasma; Rayleigh scattering; Thomson scattering

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APA (6^th Edition):

Butte, C. V. (2020). Investigation of dual-pulse laser plasmas for ignition of fuel-air mixtures. (Masters Thesis). Colorado State University. Retrieved from http://hdl.handle.net/10217/208417

Chicago Manual of Style (16^th Edition):

Butte, Carter Vincent. “Investigation of dual-pulse laser plasmas for ignition of fuel-air mixtures.” 2020. Masters Thesis, Colorado State University. Accessed March 05, 2021. http://hdl.handle.net/10217/208417.

MLA Handbook (7^th Edition):

Butte, Carter Vincent. “Investigation of dual-pulse laser plasmas for ignition of fuel-air mixtures.” 2020. Web. 05 Mar 2021.

Vancouver:

Butte CV. Investigation of dual-pulse laser plasmas for ignition of fuel-air mixtures. [Internet] [Masters thesis]. Colorado State University; 2020. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10217/208417.

Council of Science Editors:

Butte CV. Investigation of dual-pulse laser plasmas for ignition of fuel-air mixtures. [Masters Thesis]. Colorado State University; 2020. Available from: http://hdl.handle.net/10217/208417

Colorado State University

8. Aligata, Alyssa Jean. Implications of cell composition and size on the performance of microalgae ultrasonic harvesting.

Degree: MS(M.S.), Mechanical Engineering, 2018, Colorado State University

URL: http://hdl.handle.net/10217/191398

► Substantial economic challenges exist across the value chain for microalgae-based biofuels and bioproducts. Acoustic harvesting could dramatically reduce harvesting costs and directly address current energy… (more)

▼ Substantial economic challenges exist across the value chain for microalgae-based biofuels and bioproducts. Acoustic harvesting could dramatically reduce harvesting costs and directly address current energy barriers to separating algae from growth media. This technology utilizes ultrasonic standing waves to create an acoustic radiation force that, due to differences in the acoustic properties of the cells and media, causes the microalgae cells to agglomerate and settle out of the solution. The magnitude of the acoustic radiation force is directly related to the cell radius and acoustic contrast factor (ACF), the latter of which is a function of the density and compressibility of the cell. These properties can vary widely depending on the algae species, cultivation conditions, and growth stage—all of which affect the composition of the microalgae cells (e.g., lipid, carbohydrate, protein content). In this work, two methods were used to determine the ACF of microalgal cells: 1) a property measurement approach and 2) a particle tracking approach. The first method involved experimentally measuring the size distribution, density and compressibility of the cells and calculating the ACF. The second method utilized particle tracking velocimetry and a COMSOL Multiphysics model to estimate the ACF. The ACF was characterized, using both techniques, for three species—Chlamydomonas reinhardtii, Nannochloropsis salina, and Tetraselmis chuii—as a function of dynamic cellular composition over a 2-week growth period. For C. reinhardtii the lipid content increased from 26% ± 1% to 40% ± 1% from day 3 to 9, which resulted in a 43% decrease in ACF (0.056 ± 0.003 to 0.032 ± 0.001). For N. salina the lipid content increased from 25% ± 1% to 33% ± 1% from day 3 to 10, which also resulted in a 43% decrease in ACF (0.040 ± 0.002 to 0.023 ± 0.001). For T. chuii the lipid content remained relatively stable (~10%) throughout the growth period so the ACF (~0.3) did not change significantly. ACF decreases as lipid content increases because lipids have a negative ACF in growth media, whereas carbohydrates and proteins have a positive ACF. However, cell size can have a greater impact on an algal strains' responsiveness to acoustic harvesting because the net force is proportional to Φa2. Furthermore, acoustic harvesting works best for large diameter cells, provided that those cells have a nonzero ACF. T. chuii had the largest cell diameter of approximately 12 µm, while C. reinhardtii and N. salina had cell diameters of 8.5 µm and 4.3 µm, respectively. The Φa2 values for T. chuii were approximately 50× higher than the values for N. salina, which is largely due to T. chuii cells having a diameter that is 3× the diameter of N. salina cells. Composition also contributed to the higher Φa2 values for T. chuii since these cells were composed of mostly carbohydrates and had an ACF that was an order of magnitude higher than the ACF of N. salina. This research shows that acoustic harvesting has the potential to positively impact the algal biofuels value chain… Advisors/Committee Members: Marchese, Anthony (advisor), Quinn, Jason (advisor), Peebles, Christie (committee member).

Subjects/Keywords: acoustic harvesting; algae biofuels; acoustic properties; acoustic contrast factor

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APA (6^th Edition):

Aligata, A. J. (2018). Implications of cell composition and size on the performance of microalgae ultrasonic harvesting. (Masters Thesis). Colorado State University. Retrieved from http://hdl.handle.net/10217/191398

Chicago Manual of Style (16^th Edition):

Aligata, Alyssa Jean. “Implications of cell composition and size on the performance of microalgae ultrasonic harvesting.” 2018. Masters Thesis, Colorado State University. Accessed March 05, 2021. http://hdl.handle.net/10217/191398.

MLA Handbook (7^th Edition):

Aligata, Alyssa Jean. “Implications of cell composition and size on the performance of microalgae ultrasonic harvesting.” 2018. Web. 05 Mar 2021.

Vancouver:

Aligata AJ. Implications of cell composition and size on the performance of microalgae ultrasonic harvesting. [Internet] [Masters thesis]. Colorado State University; 2018. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10217/191398.

Council of Science Editors:

Aligata AJ. Implications of cell composition and size on the performance of microalgae ultrasonic harvesting. [Masters Thesis]. Colorado State University; 2018. Available from: http://hdl.handle.net/10217/191398

Colorado State University

9. Browne, Elizabeth C. Modeling ablative and regenerative cooling systems for an ethylene/ethane/nitrous oxide liquid fuel rocket engine.

Degree: MS(M.S.), Mechanical Engineering, 2020, Colorado State University

URL: http://hdl.handle.net/10217/212046

► Rocket engines create extreme conditions for any material to withstand. The combustion temperatures in rocket engines are substantially greater than the melting points of metals,… (more)

▼ Rocket engines create extreme conditions for any material to withstand. The combustion temperatures in rocket engines are substantially greater than the melting points of metals, and wall temperatures must be maintained well below the melting point to ensure structural integrity. This requirement necessitates a robust cooling system for the combustion chamber and nozzle to endure the mandated burn times. A liquid rocket engine utilizing ethane/ethylene as the fuel and nitrous oxide as the oxidizer, which is currently under development by Pioneer Astronautics, required a detailed analysis of thrust chamber cooling options. Due to the impracticality of experimentally validating the performance of each design parameter, this thesis employed computational methods to investigate two common cooling systems for rocket engines - ablative and regenerative - to determine their effectiveness at 130 and 200 chamber pressures, as prescribed by Pioneer Astronautics. Additional 1000-psi chamber pressure models were investigated for prediction validation. An analytical model was developed and utilized to elucidate the behavior of both cooling methods, while regenerative cooling was additionally analyzed using numerical modeling, coupling finite element analysis (FEA) and computational fluid dynamics (CFD) software. Simulations were created of the fluid dynamics and heat transfer within the rocket engine and coolant channels for numerous regenerative designs. The designs examined included a single-channel model utilizing only the liquid ethylene/ethane fuel as the coolant, and a dual-channel model using both the fuel and the nitrous oxide as coolants in separate sets of channels. In the single-channel regenerative cooling design, both the analytical and numerical models exhibited insufficient cooling capacity with coolant temperatures of 3-11 K above the critical temperature of 292.5 K. However, the dual-channel model provided the supplemental thermal energy absorption necessary to maintain engine wall and coolant temperatures within the allowable limits. From a design and manufacturing standpoint, ablative cooling is far simpler to implement than regenerative cooling. Although, material erosion at the throat reduces engine performance over time. Integrating ablative cooling in the combustion chamber and nozzle bell with dual-channel regenerative cooling near the throat has the potential to provide the requisite heat removal to ensure sustained material strength while maintaining all reactants in a condensed liquid phase. Advisors/Committee Members: Marchese, Anthony (advisor), Windom, Bret (advisor), Watson, Ted (committee member).

Subjects/Keywords: CFD; regenerative cooling; liquid rocket engine; ablative cooling

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APA (6^th Edition):

Browne, E. C. (2020). Modeling ablative and regenerative cooling systems for an ethylene/ethane/nitrous oxide liquid fuel rocket engine. (Masters Thesis). Colorado State University. Retrieved from http://hdl.handle.net/10217/212046

Chicago Manual of Style (16^th Edition):

Browne, Elizabeth C. “Modeling ablative and regenerative cooling systems for an ethylene/ethane/nitrous oxide liquid fuel rocket engine.” 2020. Masters Thesis, Colorado State University. Accessed March 05, 2021. http://hdl.handle.net/10217/212046.

MLA Handbook (7^th Edition):

Browne, Elizabeth C. “Modeling ablative and regenerative cooling systems for an ethylene/ethane/nitrous oxide liquid fuel rocket engine.” 2020. Web. 05 Mar 2021.

Vancouver:

Browne EC. Modeling ablative and regenerative cooling systems for an ethylene/ethane/nitrous oxide liquid fuel rocket engine. [Internet] [Masters thesis]. Colorado State University; 2020. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10217/212046.

Council of Science Editors:

Browne EC. Modeling ablative and regenerative cooling systems for an ethylene/ethane/nitrous oxide liquid fuel rocket engine. [Masters Thesis]. Colorado State University; 2020. Available from: http://hdl.handle.net/10217/212046

Colorado State University

10. Naber, Kristen Ann. FTIR spectroscopy of methyl butanoate-air and propane-air low pressure flat flames.

Degree: MS(M.S.), Mechanical Engineering, 2012, Colorado State University

URL: http://hdl.handle.net/10217/71930

► The combustion of fatty acid methyl esters (FAME) in diesel engines has been shown to produce lower emissions of carbon monoxide (CO), unburned hydrocarbons, greenhouse… (more)

▼ The combustion of fatty acid methyl esters (FAME) in diesel engines has been shown to produce lower emissions of carbon monoxide (CO), unburned hydrocarbons, greenhouse carbon dioxide (CO2), and particulate matter than petroleum based fuels. However, most diesel engine studies have shown that emission of oxides of nitrogen (NOx) typically increase for methyl ester fuels in comparison to petroleum based fuels. Many theories have been proposed to explain these NOx increases from FAME combustion but a general consensus has emerged toward two primary mechanisms: (1) the increased bulk modulus of biodiesel results in earlier fuel injection into the cylinder and/or (2) the presence of oxygen in the fuel results in a leaner (but still rich) premixed autoignition zone thereby increasing the local flame temperature during the premixed burn phase. It is well known that NOx is produced during the combustion of hydrocarbons in air from three different mechanisms: prompt NOx, thermal NOx, and via fuel bound nitrogen. Both of the mechanisms that have been proposed to explain the observed NOx increases from the combustion of FAME in diesel engines are related to the thermal NOx production route. However, no quantitative data exist on local in-cylinder temperatures and associated in-cylinder NO production during the premixed autoignition phase to experimentally verify these hypotheses. The present work is aimed at developing an experimental approach to examine a third hypothesis that suggests that the chemical structure of methyl esters results in an increase in prompt NOx in comparison to non-oxygenated hydrocarbons. This new hypothesis has the potential to be verified by conducting experiments with steady, laminar flames. Accordingly, in the present study, low pressure, flat flame burner experiments were conducted, which enabled direct temperature measurements using a thermocouple and direct species sampling using a quartz microprobe. The fuels used in the flame experiments were propane (C3H8) and methyl butanoate (C5H10O2), a small methyl ester fuel whose chemical kinetic mechanism has been the subject of substantial research in the past decade. The gas samples were directed to an FTIR spectrometer for analysis of various species including NO, CO, and CO2. Equivalence ratios of φ = 0.8, 1.0, and 1.2 were examined for both fuels. Temperatures were obtained using coated Pt-Pt/13%Rh type R thermocouples and were corrected for radiation losses. In addition to the experiments, laminar flame modeling studies were conducted using CHEMKIN for the both fuel types at each equivalence ratio using existing detailed chemical kinetic mechanisms to predict temperature and species concentrations. Because no methyl butanoate mechanisms containing detailed NOx chemistry exist, the propane/NOx chemical kinetic mechanism of Konnov and was combined with a detailed methyl butanoate mechanism Gail and coworkers. Experimental and modeling results show that nitric oxide production in the steady, premixed laminar methyl butanoate flames did not… Advisors/Committee Members: Marchese, Anthony (advisor), Catton, Kimberly (committee member), Gao, Xinfeng (committee member).

Subjects/Keywords: combustion; FAME; flat flame; FTIR; low pressure; methyl butanoate

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APA (6^th Edition):

Naber, K. A. (2012). FTIR spectroscopy of methyl butanoate-air and propane-air low pressure flat flames. (Masters Thesis). Colorado State University. Retrieved from http://hdl.handle.net/10217/71930

Chicago Manual of Style (16^th Edition):

Naber, Kristen Ann. “FTIR spectroscopy of methyl butanoate-air and propane-air low pressure flat flames.” 2012. Masters Thesis, Colorado State University. Accessed March 05, 2021. http://hdl.handle.net/10217/71930.

MLA Handbook (7^th Edition):

Naber, Kristen Ann. “FTIR spectroscopy of methyl butanoate-air and propane-air low pressure flat flames.” 2012. Web. 05 Mar 2021.

Vancouver:

Naber KA. FTIR spectroscopy of methyl butanoate-air and propane-air low pressure flat flames. [Internet] [Masters thesis]. Colorado State University; 2012. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10217/71930.

Council of Science Editors:

Naber KA. FTIR spectroscopy of methyl butanoate-air and propane-air low pressure flat flames. [Masters Thesis]. Colorado State University; 2012. Available from: http://hdl.handle.net/10217/71930

Colorado State University

11. Mohr, Jeffrey. Effect of fuel reactivity and exhaust gas recirculation on knock propensity of natural gas, The.

Degree: MS(M.S.), Mechanical Engineering, 2020, Colorado State University

URL: http://hdl.handle.net/10217/208426

► The development of high efficiency, spark ignited natural gas engines is currently limited by engine knock at high compression ratio/elevated boost pressures and misfire at… (more)

▼ The development of high efficiency, spark ignited natural gas engines is currently limited by engine knock at high compression ratio/elevated boost pressures and misfire at lean conditions/high exhaust gas recirculation (EGR) levels. The knock and misfire limits are further confounded by the wide variety in fuel reactivity observed in "pipeline quality" natural gas. In this study, a rapid compression machine was used to characterize the effects of EGR and variation in natural gas fuel reactivity on the homogeneous ignition delay, flame propagation rate, and end-gas autoignition propensity for stoichiometric natural gas/oxidizer/EGR blends. A reduced chemical kinetic mechanism was also developed to accurately model the homogeneous ignition delays measured in the Colorado State University rapid compression machine (CSU RCM). Pipeline quality natural gas with a range of chemical reactivity (68 < Methane Number < 95) was simulated using mixtures of CH4, C2H6, and C3H8. Exhaust gas recirculation gases were simulated with mixtures of Ar, CO2, CO, and NO at substitution rates of 0 to 30 mass percent. Ignition delay period under homogeneous autoignition conditions was measured at compressed pressures of 30.2 to 34.0 bar and compressed temperatures of 667 to 980 K. End-gas autoignition fraction and flame propagation rate were measured by initiating a laser spark in the center of the combustion chamber, after compression, at pressures of 30.7 to 32.7 bar and temperatures of 751 to 795 K. The results indicate that both fuel reactivity and the presence of reactive species (NO and CO) in the exhaust gas recirculation have a strong impact on end-gas autoignition fraction. A chemical kinetic mechanism was developed to predict homogeneous ignition delays for pipeline quality natural gas in a pressure and temperature range of 1-100 bar and 500-1000 K respectively. This mechanism accurately predicted measured homogeneous ignition delay in the RCM with a total average relative error of 11.0%. Advisors/Committee Members: Marchese, Anthony (advisor), Olsen, Daniel (committee member), Reardon, Kenneth (committee member).

Subjects/Keywords: energy; natural gas; spark ignited engines; exhaust gas recirculation; combustion; rapid compression machine

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APA (6^th Edition):

Mohr, J. (2020). Effect of fuel reactivity and exhaust gas recirculation on knock propensity of natural gas, The. (Masters Thesis). Colorado State University. Retrieved from http://hdl.handle.net/10217/208426

Chicago Manual of Style (16^th Edition):

Mohr, Jeffrey. “Effect of fuel reactivity and exhaust gas recirculation on knock propensity of natural gas, The.” 2020. Masters Thesis, Colorado State University. Accessed March 05, 2021. http://hdl.handle.net/10217/208426.

MLA Handbook (7^th Edition):

Mohr, Jeffrey. “Effect of fuel reactivity and exhaust gas recirculation on knock propensity of natural gas, The.” 2020. Web. 05 Mar 2021.

Vancouver:

Mohr J. Effect of fuel reactivity and exhaust gas recirculation on knock propensity of natural gas, The. [Internet] [Masters thesis]. Colorado State University; 2020. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10217/208426.

Council of Science Editors:

Mohr J. Effect of fuel reactivity and exhaust gas recirculation on knock propensity of natural gas, The. [Masters Thesis]. Colorado State University; 2020. Available from: http://hdl.handle.net/10217/208426

Colorado State University

12. Ryan, Sean Thomas. Design and fabrication of a 3-D printable counter-flow/precipitation heat exchanger for use with a novel off-grid solid state refrigeration system.

Degree: MS(M.S.), Mechanical Engineering, 2016, Colorado State University

URL: http://hdl.handle.net/10217/176606

► Off-grid refrigeration technologies are currently limited to either vapor-compression cycles driven by photovoltaics or solar thermal absorption cycles. Rebound Technologies has recently developed a novel… (more)

▼ Off-grid refrigeration technologies are currently limited to either vapor-compression cycles driven by photovoltaics or solar thermal absorption cycles. Rebound Technologies has recently developed a novel off-grid refrigeration system called SunchillTM for agricultural applications in humid environments in the developing world. The SunchillTM refrigeration system utilizes the daily high and low temperatures to drive a 24 hour refrigeration cycle. Cooling is provided by the dissolution of an endothermic salt, sodium carbonate decahydrate. Once the salt is solvated and cooling is delivered to freshly harvest crops, the system is “recharged” in a multi-step process that relies on a solar collector, an air-gap membrane unit and a heat exchanger. The heat exchanger, which is the focus of this thesis, is required to remove 36.6 MJ of heat over a twelve hour period in order to “recharge” the system. The heat exchanger is also required to transfer heat from a fresh water stream to a cold brine solution to generate the cold water necessary to submerse and cool harvested crops. To provide a sustainable technology to the target community, the feasibility of fabricating the heat exchanger via the low cost 3-D printing method of fused filament fabrication (FFF) was examined. This thesis presents the design, development, and manufacturing considerations that were performed in support of developing a waterproof, counter-flow, 3-D printable heat exchanger. Initial geometries and performance were modeled by constructing a linear thermal resistance network with truncating temperatures of 30°C (saturated brine temperature) and 18°C (average daily low temperature). The required surface area of the heat exchanger was found to be 20.46 m2 to remove the required 36.6 MJ of heat. Iterative print tests were conducted to arrive at the wall thickness, hexagon shape, and double wall structure of the heat exchanger. A laboratory-scale heat exchanger was fabricated using a Lulzbot Taz 4 printer from acrylonitrile butadiene styrene (ABS) polymer. Performance was verified empirically for the laboratory-scale unit. A heat transfer rate of 22.8 W was obtained at a flow rate of 0.00075 kg/s. The results of this thesis demonstrate the feasibility of manufacturing low cost heat exchangers using additive manufacturing techniques. Advisors/Committee Members: Marchese, Anthony (advisor), Kirkpatrick, Allan (committee member), Sharvelle, Sybil (committee member).

Subjects/Keywords: polymer heat exchanger; 3D printing

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APA (6^th Edition):

Ryan, S. T. (2016). Design and fabrication of a 3-D printable counter-flow/precipitation heat exchanger for use with a novel off-grid solid state refrigeration system. (Masters Thesis). Colorado State University. Retrieved from http://hdl.handle.net/10217/176606

Chicago Manual of Style (16^th Edition):

Ryan, Sean Thomas. “Design and fabrication of a 3-D printable counter-flow/precipitation heat exchanger for use with a novel off-grid solid state refrigeration system.” 2016. Masters Thesis, Colorado State University. Accessed March 05, 2021. http://hdl.handle.net/10217/176606.

MLA Handbook (7^th Edition):

Ryan, Sean Thomas. “Design and fabrication of a 3-D printable counter-flow/precipitation heat exchanger for use with a novel off-grid solid state refrigeration system.” 2016. Web. 05 Mar 2021.

Vancouver:

Ryan ST. Design and fabrication of a 3-D printable counter-flow/precipitation heat exchanger for use with a novel off-grid solid state refrigeration system. [Internet] [Masters thesis]. Colorado State University; 2016. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10217/176606.

Council of Science Editors:

Ryan ST. Design and fabrication of a 3-D printable counter-flow/precipitation heat exchanger for use with a novel off-grid solid state refrigeration system. [Masters Thesis]. Colorado State University; 2016. Available from: http://hdl.handle.net/10217/176606

Colorado State University

13. Armstrong, Kristina Ochsner. Analysis of life cycle assessment of food/energy/waste systems and development and analysis of microalgae cultivation/wastewater treatment inclusive system.

Degree: MS(M.S.), Mechanical Engineering, 2013, Colorado State University

URL: http://hdl.handle.net/10217/80202

► Across the world, crises in food, energy, land and water resources, as well as waste and greenhouse gas accumulation are inspiring research into the interactions… (more)

▼ Across the world, crises in food, energy, land and water resources, as well as waste and greenhouse gas accumulation are inspiring research into the interactions among these environmental pressures. In the food/energy/waste problem set, most of the research is focused on describing the antagonistic relationships between food, energy and waste; these relationships are often analyzed with life cycle assessment (LCA). These analyses often include reporting of metrics of environmental performance with few functional units, often focusing on energy use, productivity and environmental impact while neglecting water use, food nutrition and safety. Additionally, they are often attributional studies with small scope which report location-specific parameters only. This thesis puts forth a series of recommendations to amend the current practice of LCA to combat these limitations and then utilizes these suggestions to analyze a synergistic food/waste/energy system. As an example analysis, this thesis describes the effect of combining wastewater treatment and microalgae cultivation on the productivity and scalability of the synergistic system. To ameliorate the high nutrient and water demands of microalgae cultivation, many studies suggest that microalgae be cultivated in wastewater so as to achieve large scale and low environmental costs. While cultivation studies have found this to be true, none explore the viability of the substitution in terms of productivity and scale-up. The results of this study suggest that while the integrated system may be suitable for low-intensity microalgae cultivation, for freshwater microalgae species or wastewater treatment it is not suitable for high intensity salt water microalgae cultivation. This study shows that the integration could result in reduced lipid content, high wastewater requirements, no greenhouse gas emissions benefit and only a small energy benefit. Advisors/Committee Members: Bradley, Thomas H. (advisor), De Long, Susan (committee member), Marchese, Anthony (committee member).

Subjects/Keywords: biofuels; wastewater; microalgae; life cycle analysis; LCA

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APA (6^th Edition):

Armstrong, K. O. (2013). Analysis of life cycle assessment of food/energy/waste systems and development and analysis of microalgae cultivation/wastewater treatment inclusive system. (Masters Thesis). Colorado State University. Retrieved from http://hdl.handle.net/10217/80202

Chicago Manual of Style (16^th Edition):

Armstrong, Kristina Ochsner. “Analysis of life cycle assessment of food/energy/waste systems and development and analysis of microalgae cultivation/wastewater treatment inclusive system.” 2013. Masters Thesis, Colorado State University. Accessed March 05, 2021. http://hdl.handle.net/10217/80202.

MLA Handbook (7^th Edition):

Armstrong, Kristina Ochsner. “Analysis of life cycle assessment of food/energy/waste systems and development and analysis of microalgae cultivation/wastewater treatment inclusive system.” 2013. Web. 05 Mar 2021.

Vancouver:

Armstrong KO. Analysis of life cycle assessment of food/energy/waste systems and development and analysis of microalgae cultivation/wastewater treatment inclusive system. [Internet] [Masters thesis]. Colorado State University; 2013. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10217/80202.

Council of Science Editors:

Armstrong KO. Analysis of life cycle assessment of food/energy/waste systems and development and analysis of microalgae cultivation/wastewater treatment inclusive system. [Masters Thesis]. Colorado State University; 2013. Available from: http://hdl.handle.net/10217/80202

Colorado State University

14. Wise, Daniel M. Investigation into producer gas utilization in high performance natural gas engines.

Degree: PhD, Mechanical Engineering, 2013, Colorado State University

URL: http://hdl.handle.net/10217/78876

► A wide range of fuels are used in industrial gas fueled engines including well-head gas, pipeline natural gas, producer gas, coal gas, digester gas, landfill… (more)

▼ A wide range of fuels are used in industrial gas fueled engines including well-head gas, pipeline natural gas, producer gas, coal gas, digester gas, landfill gas, and liquefied petroleum gas. Many industrial gas fueled engines operate both at high power density for increased efficiency and at ultra-lean air-fuel ratios for low NOx emissions. These two conditions require that engine operation occurs in a narrow air-fuel ratio band between the limits of misfire and the initiation of knock. The ability to characterize these limits for a given fuel is essential for efficient and effective engine operation. This work pursues two primary research objectives: (1) to characterize producer gas blends by developing prognostic tools with respect to a given blend's resistance to knock and (2) to develop a process to determine knock onset for a given fuel gas through direct indication from pressure transducer data at varied air-fuel ratios (ranging from stoichiometric to ultra-lean) as well as varied intake conditions (ranging from naturally aspirated to boosted intake pressures replicating turbocharged engines) and to quantitatively characterize the knock event using discreet and repeatable metrics derived from the analysis of the data. Methane number determination for natural gas blends is traditionally performed with research engines at stoichiometric conditions where the onset of knock is identified through subjective audible indication. To more closely replicate the operating conditions of a typical industrial engine, a Cooperative Fuel Research (CFR F2) engine is modified for boosted fuel/air intake and variable exhaust back pressure (to simulate turbocharger operation) with the incorporation of piezoelectric pressure transducers at the cylinder head to allow quantitative analysis of cylinder pressure conditions and transients precursive to, during, and following a knock event of varying magnitude. The interpretation of this data provides for evaluation of unique analytical methods to quantify and characterize engine knock under these conditions. In the course of this study an objective and consistent method for measuring methane number is developed, measured methane number for a total of 35 producer gas blends is provided, and a prognostic tool for predicting methane number, utilizing neural networks, is presented. Advisors/Committee Members: Olsen, Daniel B. (advisor), Caille, Gary (committee member), Marchese, Anthony (committee member), Sharvelle, Sybil (committee member).

Subjects/Keywords: knock; producer gas; methane number

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APA (6^th Edition):

Wise, D. M. (2013). Investigation into producer gas utilization in high performance natural gas engines. (Doctoral Dissertation). Colorado State University. Retrieved from http://hdl.handle.net/10217/78876

Chicago Manual of Style (16^th Edition):

Wise, Daniel M. “Investigation into producer gas utilization in high performance natural gas engines.” 2013. Doctoral Dissertation, Colorado State University. Accessed March 05, 2021. http://hdl.handle.net/10217/78876.

MLA Handbook (7^th Edition):

Wise, Daniel M. “Investigation into producer gas utilization in high performance natural gas engines.” 2013. Web. 05 Mar 2021.

Vancouver:

Wise DM. Investigation into producer gas utilization in high performance natural gas engines. [Internet] [Doctoral dissertation]. Colorado State University; 2013. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10217/78876.

Council of Science Editors:

Wise DM. Investigation into producer gas utilization in high performance natural gas engines. [Doctoral Dissertation]. Colorado State University; 2013. Available from: http://hdl.handle.net/10217/78876

Colorado State University

15. Doyle, Jake Downin. Evaluation of a non-thermal plasma generator for plasma-assisted combustion in an oil burner.

Degree: MS(M.S.), Mechanical Engineering, 2013, Colorado State University

URL: http://hdl.handle.net/10217/79041

► The addition of plasma to a combustion system has the potential to increase the combustion efficiency and reduce harmful emissions by reforming hydrocarbon fuels. The… (more)

Subjects/Keywords: oil burner; plasma fuel reforming; plasma assisted combustion; plasma

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APA (6^th Edition):

Doyle, J. D. (2013). Evaluation of a non-thermal plasma generator for plasma-assisted combustion in an oil burner. (Masters Thesis). Colorado State University. Retrieved from http://hdl.handle.net/10217/79041

Chicago Manual of Style (16^th Edition):

Doyle, Jake Downin. “Evaluation of a non-thermal plasma generator for plasma-assisted combustion in an oil burner.” 2013. Masters Thesis, Colorado State University. Accessed March 05, 2021. http://hdl.handle.net/10217/79041.

MLA Handbook (7^th Edition):

Doyle, Jake Downin. “Evaluation of a non-thermal plasma generator for plasma-assisted combustion in an oil burner.” 2013. Web. 05 Mar 2021.

Vancouver:

Doyle JD. Evaluation of a non-thermal plasma generator for plasma-assisted combustion in an oil burner. [Internet] [Masters thesis]. Colorado State University; 2013. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10217/79041.

Council of Science Editors:

Doyle JD. Evaluation of a non-thermal plasma generator for plasma-assisted combustion in an oil burner. [Masters Thesis]. Colorado State University; 2013. Available from: http://hdl.handle.net/10217/79041

Colorado State University

16. Badrinarayanan, Koushik. Performance evaluation of multiple oxidation catalysts on a lean burn natural gas engine.

Degree: MS(M.S.), Mechanical Engineering, 2012, Colorado State University

URL: http://hdl.handle.net/10217/67555

► Emission from lean burn natural gas engines used for power generation and gas compression are major contributors to air pollution. Two-way catalysts or oxidation catalysts… (more)

▼ Emission from lean burn natural gas engines used for power generation and gas compression are major contributors to air pollution. Two-way catalysts or oxidation catalysts are the common after-treatment systems used on lean burn natural gas engines to reduce CO, VOCs and formaldehyde emissions. The performance of the oxidation catalysts is dependent on operating parameters like catalyst temperature and space velocity. For this study, a part of the exhaust from a Waukesha VGF-18 GL lean burn natural gas engine was flowed through a catalyst slipstream system to access the performance of the oxidation catalysts. The slipstream is used to reduce the size of the catalysts and to allow precise control of temperature and space velocity. Analyzers used include Rosemount 5-gas emissions bench, Nicolet Fourier Transform Infra-Red spectrometer and HP 5890 Series II Gas Chromatograph. The oxidation catalysts were degreened at 1200°F (650°C) for 24 hours prior to performance testing. The conversion efficiencies for the emission species varied among the oxidation catalysts tested from different vendors. Therefore, the performance of all the oxidation catalysts is not the same for this application. Most oxidation catalysts showed over 90% maximum conversion efficiencies on CO, VOCs and formaldehyde. Saturated hydrocarbons such as propane were difficult to oxidize in an oxidation catalyst due to high activation energy. High VOC oxidation was noticed on all catalysts, with maximum conversion efficiency at 80%. VOC reduction efficiency was limited by propane emission in the exhaust for the catalyst temperatures tested. Additional formulations need to be developed for oxidation catalysts to increase VOC reduction efficiency. Oxidation of NO to NO2 was observed on most oxidation catalysts; this reaction is favored based on chemical equilibrium. Variation in space velocity showed very little effect on the conversion efficiencies. Most species showed over 90% conversion efficiency during the space velocity sweep. The oxidation catalysts showed increasing CH2O conversion efficiency with decreasing space velocity. No change on performance of the oxidation catalysts on conversion of emission species was noticed for varying space velocities after conversion efficiencies reached 90%. Thus, adding more catalyst volume may not increase the reduction efficiency of emission species. Varying cell density showed very little effect on performance of the oxidation catalysts. The friction factor correlation showed the friction factor is inversely proportional to cell density. Advisors/Committee Members: Olsen, Daniel B. (advisor), Marchese, Anthony (committee member), De Miranda, Michael A. (committee member).

Subjects/Keywords: exhaust after-treatment systems; VOC emission; oxidation catalysts; natural gas engine; engine emission

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APA (6^th Edition):

Badrinarayanan, K. (2012). Performance evaluation of multiple oxidation catalysts on a lean burn natural gas engine. (Masters Thesis). Colorado State University. Retrieved from http://hdl.handle.net/10217/67555

Chicago Manual of Style (16^th Edition):

Badrinarayanan, Koushik. “Performance evaluation of multiple oxidation catalysts on a lean burn natural gas engine.” 2012. Masters Thesis, Colorado State University. Accessed March 05, 2021. http://hdl.handle.net/10217/67555.

MLA Handbook (7^th Edition):

Badrinarayanan, Koushik. “Performance evaluation of multiple oxidation catalysts on a lean burn natural gas engine.” 2012. Web. 05 Mar 2021.

Vancouver:

Badrinarayanan K. Performance evaluation of multiple oxidation catalysts on a lean burn natural gas engine. [Internet] [Masters thesis]. Colorado State University; 2012. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10217/67555.

Council of Science Editors:

Badrinarayanan K. Performance evaluation of multiple oxidation catalysts on a lean burn natural gas engine. [Masters Thesis]. Colorado State University; 2012. Available from: http://hdl.handle.net/10217/67555

Colorado State University

17. Franka, Isaiah S. Cavity enhanced instruments for detection of hydrogen chloride and aerosol optical extinction.

Degree: MS(M.S.), Mechanical Engineering, 2013, Colorado State University

URL: http://hdl.handle.net/10217/79036

► This thesis concerns the development of cavity enhanced instruments for atmospheric science studies. Hydrochloric acid (HCl) is an important reservoir species for active halogens which… (more)

Subjects/Keywords: radiative forcing; cavity ring-down spectroscopy; ozone; hydrogen chloride; aerosol optical extinction; cavity enhanced absorption spectroscopy

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APA (6^th Edition):

Franka, I. S. (2013). Cavity enhanced instruments for detection of hydrogen chloride and aerosol optical extinction. (Masters Thesis). Colorado State University. Retrieved from http://hdl.handle.net/10217/79036

Chicago Manual of Style (16^th Edition):

Franka, Isaiah S. “Cavity enhanced instruments for detection of hydrogen chloride and aerosol optical extinction.” 2013. Masters Thesis, Colorado State University. Accessed March 05, 2021. http://hdl.handle.net/10217/79036.

MLA Handbook (7^th Edition):

Franka, Isaiah S. “Cavity enhanced instruments for detection of hydrogen chloride and aerosol optical extinction.” 2013. Web. 05 Mar 2021.

Vancouver:

Franka IS. Cavity enhanced instruments for detection of hydrogen chloride and aerosol optical extinction. [Internet] [Masters thesis]. Colorado State University; 2013. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10217/79036.

Council of Science Editors:

Franka IS. Cavity enhanced instruments for detection of hydrogen chloride and aerosol optical extinction. [Masters Thesis]. Colorado State University; 2013. Available from: http://hdl.handle.net/10217/79036

Colorado State University

18. Martinez Morett, David. Reduced chemical kinetic mechanism for computational fluid dynamics simulations of high brake mean effective pressure, lean-burn natural gas engines, A.

Degree: MS(M.S.), Mechanical Engineering, 2012, Colorado State University

URL: http://hdl.handle.net/10217/78749

► Recent developments in numerical techniques and computational processing power now permit time-dependent, multi-dimensional computational fluid dynamics (CFD) calculations with detailed chemical kinetic mechanisms using commercially… (more)

▼ Recent developments in numerical techniques and computational processing power now permit time-dependent, multi-dimensional computational fluid dynamics (CFD) calculations with detailed chemical kinetic mechanisms using commercially available software. Such computations have the potential to be highly effective tools for designing lean-burn, high brake mean effective pressure (BMEP) natural gas engines that achieve high fuel efficiency and low emissions. Specifically, these CFD simulations can provide the analytical tools required to design highly optimized natural gas engine components such as pistons, intake ports, pre-combustion chambers, fuel systems and ignition systems. To accurately model the transient, multi-dimensional chemically reacting flows present in these systems, detailed chemical kinetic mechanisms are needed that accurately reproduce measured combustion data at high pressures and lean conditions, but are of reduced size to enable reasonable computational times. Prior to the present study, these CFD models could not be used as accurate design tools for application in high BMEP lean-burn gas engines because existing reduced chemical kinetic mechanisms failed to accurately reproduce experimental flame speed and ignition delay data for natural gas at high pressure (40 atm and higher) and lean (0.6 equivalence ratio and lower) conditions. Existing methane oxidation mechanisms had typically been validated with experimental conditions at atmospheric and intermediate pressures (1 to 20 atm) and relatively rich stoichiometry. Accordingly, these kinetic mechanisms were not adequate for CFD simulation of natural gas combustion for which elevated pressures and very lean conditions are typical. This thesis describes an analysis, based on experimental data, of the laminar flame speed computed from numerous, detailed chemical kinetic mechanisms for methane combustion at pressures and equivalence ratios necessary for accurate high BMEP, lean-burn natural gas engine modeling. A reduced mechanism that was shown previously to best match data at moderately lean and high pressure conditions was updated for the conditions of interest by performing sensitivity analysis using CHEMKIN. The reaction rate constants from the most sensitive reactions were appropriately adjusted to obtain better agreement at high pressure lean conditions. An evaluation of two new reduced chemical kinetic mechanisms for methane combustion was performed using Converge CFD software. The results were compared to engine data and a significant improvement on combustion performance prediction was obtained with the new mechanisms. Advisors/Committee Members: Marchese, Anthony J. (advisor), Olsen, Daniel B. (committee member), Dandy, David S. (committee member).

Subjects/Keywords: combustion; simulation; natural gas; engine

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APA (6^th Edition):

Martinez Morett, D. (2012). Reduced chemical kinetic mechanism for computational fluid dynamics simulations of high brake mean effective pressure, lean-burn natural gas engines, A. (Masters Thesis). Colorado State University. Retrieved from http://hdl.handle.net/10217/78749

Chicago Manual of Style (16^th Edition):

Martinez Morett, David. “Reduced chemical kinetic mechanism for computational fluid dynamics simulations of high brake mean effective pressure, lean-burn natural gas engines, A.” 2012. Masters Thesis, Colorado State University. Accessed March 05, 2021. http://hdl.handle.net/10217/78749.

MLA Handbook (7^th Edition):

Martinez Morett, David. “Reduced chemical kinetic mechanism for computational fluid dynamics simulations of high brake mean effective pressure, lean-burn natural gas engines, A.” 2012. Web. 05 Mar 2021.

Vancouver:

Martinez Morett D. Reduced chemical kinetic mechanism for computational fluid dynamics simulations of high brake mean effective pressure, lean-burn natural gas engines, A. [Internet] [Masters thesis]. Colorado State University; 2012. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10217/78749.

Council of Science Editors:

Martinez Morett D. Reduced chemical kinetic mechanism for computational fluid dynamics simulations of high brake mean effective pressure, lean-burn natural gas engines, A. [Masters Thesis]. Colorado State University; 2012. Available from: http://hdl.handle.net/10217/78749

Colorado State University

19. Luck, Benjamin Kendell. Long duration measurements of pneumatic controller emissions on onshore natural gas gathering stations.

Degree: MS(M.S.), Systems Engineering, 2019, Colorado State University

URL: http://hdl.handle.net/10217/195294

► Over the last 15 years, advances in hydraulic fracturing have led to a boom of natural gas production the United States and abroad. The combustion… (more)

▼ Over the last 15 years, advances in hydraulic fracturing have led to a boom of natural gas production the United States and abroad. The combustion of natural gas produces less carbon dioxide (CO2) than the combustion of other fossil fuels per unit of energy released, making it an attractive option for reducing emissions from power generation and transportation industries. Uncombusted methane (CH4) has a global warming potential (GWP) of 86 times that of CO2 on 20 year time scales and a GWP of global warming potential 32 times greater than CO2 on a 100 year time scale. The increase in supply chain throughput has led to concerns regarding the greenhouse gas contributions of CH4 from accidental or operational leaks from natural gas infrastructure. Automated, pneumatic actuated valves are used to control process variables on stations in all sectors of the natural gas industry. Pneumatic valve controllers (PCs) vent natural gas to the atmosphere during their normal operation and are a significant source of fugitive emissions from the natural gas supply chain. This paper outlines the work that was done to improve the characterization of emissions from PCs using long duration measurements. This work was performed as part of the Department of Energy funded Gathering Emission Factor (GEF) study. A thermal mass flow meter based emission measurement system was developed to perform direct measurements of pneumatic controller emissions over multiday periods. This measurement system was developed based on methods used in previous studies, with design modifications made to meet site safety regulations, power supply constraints and measurement duration targets. Emissions were measured from 72 PCs at 16 gathering compressor stations between June, 2017 and May, 2018. The average emission rate of 72 PCs was 10.86 scfh [+4.31/-3.60], which is 91.2% of the EPA's current emission factor for PCs on gathering compressor stations. The mean measurement duration of these 72 samples was 76.8 hours. Due to potential biases associated with flow meter errors, updates to EPA emission factors based on these data are not proposed. However, because all previous studies to quantify PC emissions used short sampling times (typically ≤15 minutes) the long duration measurements provided insight into previously unobserved PC emissions behavior. A panel of industry experts assessed the emissions recordings and found that 30 PCs (42% of measured devices) had emissions patterns or rates that were inconsistent with their design. 73% of emissions measured during this study were attributed to these 30 PCs that were malfunctioning from an emissions perspective. It was also found that PC emission rates are more variable over time than previously thought. Due to this high temporal variability, the short duration observations currently used by leak detection programs to identify malfunctioning equipment have a low probability of providing accurate characterizations of PC emissions. Many natural gas companies are investigating ways to improve the efficiency of their… Advisors/Committee Members: Quinn, Jason (advisor), Zimmerle, Daniel (advisor), Marchese, Anthony (committee member), von Fischer, Joseph (committee member).

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APA (6^th Edition):

Luck, B. K. (2019). Long duration measurements of pneumatic controller emissions on onshore natural gas gathering stations. (Masters Thesis). Colorado State University. Retrieved from http://hdl.handle.net/10217/195294

Chicago Manual of Style (16^th Edition):

Luck, Benjamin Kendell. “Long duration measurements of pneumatic controller emissions on onshore natural gas gathering stations.” 2019. Masters Thesis, Colorado State University. Accessed March 05, 2021. http://hdl.handle.net/10217/195294.

MLA Handbook (7^th Edition):

Luck, Benjamin Kendell. “Long duration measurements of pneumatic controller emissions on onshore natural gas gathering stations.” 2019. Web. 05 Mar 2021.

Vancouver:

Luck BK. Long duration measurements of pneumatic controller emissions on onshore natural gas gathering stations. [Internet] [Masters thesis]. Colorado State University; 2019. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10217/195294.

Council of Science Editors:

Luck BK. Long duration measurements of pneumatic controller emissions on onshore natural gas gathering stations. [Masters Thesis]. Colorado State University; 2019. Available from: http://hdl.handle.net/10217/195294

Colorado State University

20. Prapas, Jason. Toward the understanding and optimization of chimneys for buoyantly driven biomass stoves.

Degree: PhD, Mechanical Engineering, 2013, Colorado State University

URL: http://hdl.handle.net/10217/80968

► The vast majority of indoor combustion devices in the developed world make use of stacks (flues, vents, chimneys, smokestacks) to channel flue gases out of… (more)

▼ The vast majority of indoor combustion devices in the developed world make use of stacks (flues, vents, chimneys, smokestacks) to channel flue gases out of the operator space. In the developing world, where indoor air pollution kills several million people every year, the use of chimneys with biomass cooking and heating stoves has been met with limited success and a high level of controversy. Due to a lack of theoretical understanding, design criteria, poorly executed installation practices, and/or insufficient maintenance routines, many chimney stoves have exhibited inadequate indoor emissions reductions in addition to low thermal efficiencies. This work aims (a) shed light on the physical phenomenon of the "stack effect" as it pertains to dynamic, non-adiabatic, buoyancy-driven stoves (b) apply new understanding toward the optimization of two types of biomass chimney stoves: plancha or griddle type stoves popular in Central America and two-pot stoves common in South America. A numerical heat and fluid flow model was developed that takes into account the highly-coupled variables and dynamic nature of such systems. With a comprehensive physical model, parameter studies were conducted to determine how several field-relevant variables influence the performance of stack-outfitted systems. These parameters include, but are not limited to: power/wood consumption rate, chimney geometry, stove geometry, material properties, heat transfer, and ambient conditions. An instrumented experimental chimney was built to monitor relationships between air flow, differential pressure, gas temperatures, emissions, and thermal efficiency. The draft provided by chimneys was found to have a strong influence over the bulk air-to-fuel ratio of buoyantly-driven cookstoves, greatly affecting the stove's overall performance by affecting gas temperatures, emissions, and efficiency. Armed with new information from the modeling and experimental work, two new stoves were designed and optimized to have significant reductions in fuel use and emissions. Advisors/Committee Members: Willson, Bryan (advisor), DeFoort, Morgan (advisor), Marchese, Anthony (committee member), Peel, Jennifer (committee member).

Subjects/Keywords: biomass; stove; draft; chimney

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APA (6^th Edition):

Prapas, J. (2013). Toward the understanding and optimization of chimneys for buoyantly driven biomass stoves. (Doctoral Dissertation). Colorado State University. Retrieved from http://hdl.handle.net/10217/80968

Chicago Manual of Style (16^th Edition):

Prapas, Jason. “Toward the understanding and optimization of chimneys for buoyantly driven biomass stoves.” 2013. Doctoral Dissertation, Colorado State University. Accessed March 05, 2021. http://hdl.handle.net/10217/80968.

MLA Handbook (7^th Edition):

Prapas, Jason. “Toward the understanding and optimization of chimneys for buoyantly driven biomass stoves.” 2013. Web. 05 Mar 2021.

Vancouver:

Prapas J. Toward the understanding and optimization of chimneys for buoyantly driven biomass stoves. [Internet] [Doctoral dissertation]. Colorado State University; 2013. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10217/80968.

Council of Science Editors:

Prapas J. Toward the understanding and optimization of chimneys for buoyantly driven biomass stoves. [Doctoral Dissertation]. Colorado State University; 2013. Available from: http://hdl.handle.net/10217/80968

Colorado State University

21. Loveldi, Nathan. Development of a solid human waste semigasifier burner for use in developing countries.

Degree: MS(M.S.), Mechanical Engineering, 2014, Colorado State University

URL: http://hdl.handle.net/10217/83992

► Recent estimates suggest that approximately 40% of the world's population does not have access to an adequate sanitation system. This lack of access is one… (more)

Subjects/Keywords: biomass; combustion; downdraft; gasification; gasifier; solid waste

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APA (6^th Edition):

Loveldi, N. (2014). Development of a solid human waste semigasifier burner for use in developing countries. (Masters Thesis). Colorado State University. Retrieved from http://hdl.handle.net/10217/83992

Chicago Manual of Style (16^th Edition):

Loveldi, Nathan. “Development of a solid human waste semigasifier burner for use in developing countries.” 2014. Masters Thesis, Colorado State University. Accessed March 05, 2021. http://hdl.handle.net/10217/83992.

MLA Handbook (7^th Edition):

Loveldi, Nathan. “Development of a solid human waste semigasifier burner for use in developing countries.” 2014. Web. 05 Mar 2021.

Vancouver:

Loveldi N. Development of a solid human waste semigasifier burner for use in developing countries. [Internet] [Masters thesis]. Colorado State University; 2014. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10217/83992.

Council of Science Editors:

Loveldi N. Development of a solid human waste semigasifier burner for use in developing countries. [Masters Thesis]. Colorado State University; 2014. Available from: http://hdl.handle.net/10217/83992

Colorado State University

22. Fagerstone, Kelly Dawn. Measurement of direct nitrous oxide emissions from microalgae cultivation under oxic and anoxic conditions.

Degree: MS(M.S.), Mechanical Engineering, 2011, Colorado State University

URL: http://hdl.handle.net/10217/46735

► Lifecycle assessments (LCA) of microalgae-based biofuels have demonstrated net greenhouse gas (GHG) emissions reductions, but limited data exist on direct emissions of GHG's from microalgae… (more)

▼ Lifecycle assessments (LCA) of microalgae-based biofuels have demonstrated net greenhouse gas (GHG) emissions reductions, but limited data exist on direct emissions of GHG's from microalgae cultivation systems such as open raceway ponds (ORP) or photobioreactors (PBR). For example, nitrous oxide (N2O) is a potent GHG that has been detected from microalgae cultivation. However, N2O emissions have not been experimentally quantified to determine their impact on overall lifecycle assessment of the microalgae-to-biofuels process. Theoretical calculations using the Intergovernmental Panel on Climate Change standards for terrestrial crops (1% of available nitrogen applied as fertilizer is converted to N2O) suggest the potential for significant levels of N2O from microalgae cultivation. In this study, microalgae species Nannochloropsis salina was cultivated with nitrate under conditions representative of PBR and ORP growth conditions with diurnal light-dark cycling. To examine the effect of dissolved oxygen on N2O emissions, experiments were conducted with an air headspace and nitrogen headspace, respectively. During these experiments N2O emissions were quantified utilizing Fourier Transform Infrared spectrometry. Under a nitrogen headspace, N2O emissions were elevated during dark periods and minimal during light periods. Under an air headspace, N2O emissions were negligible for both the light and dark periods. The experimental results show that N2O production was induced by anoxic conditions with nitrate present in the growth media, suggesting that N2O was produced by denitrifying bacteria within the microalgal growth media. The presence of denitrifying bacteria was verified through PCR-based detection of norB genes, which encode bacterial enzymes that produce N2O. Furthermore, antibiotic treatments inhibited N2O emissions. Application of these results to LCA and potential strategies for management of growth systems to reduce N2O emissions are discussed. Advisors/Committee Members: Marchese, Anthony John, 1967- (advisor), Bradley, Thomas H. (advisor), De Long, Susan K. (committee member).

Subjects/Keywords: nitrous oxide; biofuel; greenhouse gas; lifecycle analysis; microalgae

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APA (6^th Edition):

Fagerstone, K. D. (2011). Measurement of direct nitrous oxide emissions from microalgae cultivation under oxic and anoxic conditions. (Masters Thesis). Colorado State University. Retrieved from http://hdl.handle.net/10217/46735

Chicago Manual of Style (16^th Edition):

Fagerstone, Kelly Dawn. “Measurement of direct nitrous oxide emissions from microalgae cultivation under oxic and anoxic conditions.” 2011. Masters Thesis, Colorado State University. Accessed March 05, 2021. http://hdl.handle.net/10217/46735.

MLA Handbook (7^th Edition):

Fagerstone, Kelly Dawn. “Measurement of direct nitrous oxide emissions from microalgae cultivation under oxic and anoxic conditions.” 2011. Web. 05 Mar 2021.

Vancouver:

Fagerstone KD. Measurement of direct nitrous oxide emissions from microalgae cultivation under oxic and anoxic conditions. [Internet] [Masters thesis]. Colorado State University; 2011. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10217/46735.

Council of Science Editors:

Fagerstone KD. Measurement of direct nitrous oxide emissions from microalgae cultivation under oxic and anoxic conditions. [Masters Thesis]. Colorado State University; 2011. Available from: http://hdl.handle.net/10217/46735

Colorado State University

23. L'Orange, Christian. Development of numerical tools for characterizing and quantifying biomass cookstove impact, The.

Degree: PhD, Mechanical Engineering, 2013, Colorado State University

URL: http://hdl.handle.net/10217/80160

► Biomass cookstove use can be damaging to both human health and the global climate. In an effort to minimize these impacts, numerous programs are working… (more)

▼ Biomass cookstove use can be damaging to both human health and the global climate. In an effort to minimize these impacts, numerous programs are working to disseminate improved biomass cookstoves. However, few programs have achieved extensive success towards improving either climate or health. One reason programs have only resulted in limited improvements has been the sector's inability to quantify cookstove performance. A numeric tool has been developed for characterizing biomass cookstove performance. This dissertation documents the development of that tool. The document is comprised of three components: (i) the critical analysis of the uncertainty associated with current methods for cookstove field-testing, (ii) the development and validation of a probabilistic impact model for biomass cookstoves, and (iii) the application of these numerical tools to quantify cookstove impact. Biomass cookstoves have traditionally been evaluated empirically. Cookstoves are tested in both the field and the laboratory, with each approach having advantages and limitations. Neither laboratory nor field testing are sufficient, however, for quantifying cookstove impact. Field-testing provides invaluable data on cookstove use but is limited by the large variability typically seen in the results. Drawing conclusions from field tests is challenging due to this variability. Many groups attempt to address testing variability by increasing the number of test replicates conducted. A numeric model was developed to determine the number of test replicates required to quantify cookstove performance in field settings. Because of the large number of test replicates required to have statistical confidence in field-based data, an improved method of quantifying biomass cookstove performance is needed. Therefore, to address this need a probabilistic Monte Carlo prediction model was developed to quantify cookstove performance. The intention of the model is to serve as a tool for predicting the impact of various cookstove designs. The model integrates various facets of existing cookstove performance knowledge in more a cohesive fashion. Model simulations were compared to experimental studies to validate this approach. Numeric tools are only valuable if they result in useful information; for example, information that allows informed decisions to be made. The potential of numeric models to provide valuable information for cookstove programs has been demonstrated by simulating the performance of multiple cookstove designs. Three improved cookstoves designs have been compared to a traditional three-stone fire. Each design was evaluated for multiple scenarios, use patterns, and locations. The impact of each design (in regard to climate and health) was then quantified and monetized. This exercise yielded two important findings. First, consideration of location and context is critical when comparing the performance of cookstoves. Second, numeric models can be used as highly informative tools to support decision-making in the cookstove sector. Empirical… Advisors/Committee Members: Willson, Bryan (advisor), DeFoort, Morgan (advisor), Marchese, Anthony (committee member), Volckens, John (committee member).

Subjects/Keywords: biomass; combustion; cookstove; modeling; Monte Carlo

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APA (6^th Edition):

L'Orange, C. (2013). Development of numerical tools for characterizing and quantifying biomass cookstove impact, The. (Doctoral Dissertation). Colorado State University. Retrieved from http://hdl.handle.net/10217/80160

Chicago Manual of Style (16^th Edition):

L'Orange, Christian. “Development of numerical tools for characterizing and quantifying biomass cookstove impact, The.” 2013. Doctoral Dissertation, Colorado State University. Accessed March 05, 2021. http://hdl.handle.net/10217/80160.

MLA Handbook (7^th Edition):

L'Orange, Christian. “Development of numerical tools for characterizing and quantifying biomass cookstove impact, The.” 2013. Web. 05 Mar 2021.

Vancouver:

L'Orange C. Development of numerical tools for characterizing and quantifying biomass cookstove impact, The. [Internet] [Doctoral dissertation]. Colorado State University; 2013. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10217/80160.

Council of Science Editors:

L'Orange C. Development of numerical tools for characterizing and quantifying biomass cookstove impact, The. [Doctoral Dissertation]. Colorado State University; 2013. Available from: http://hdl.handle.net/10217/80160

Colorado State University

24. Baumgardner, Marc E. Characterizing fuel reactivity in advanced internal combustion engines.

Degree: PhD, Mechanical Engineering, 2014, Colorado State University

URL: http://hdl.handle.net/10217/82656

► The urgent need to increase efficiency and reduce exhaust emissions from internal combustion engines has resulted in an increased interest in alternative combustion modes. Premixed… (more)

▼ The urgent need to increase efficiency and reduce exhaust emissions from internal combustion engines has resulted in an increased interest in alternative combustion modes. Premixed or partially premixed compression ignition modes, such as homogeneous-charge compression ignition (HCCI), reactivity-controlled compression ignition (RCCI) and multi-zone stratified compression ignition (MSCI) have been a particular focus because of their potential to deliver enhanced fuel efficiency and meet exhaust emissions mandates without the addition of costly after-treatment technologies. For HCCI and other single fuel, partially premixed compression ignition schemes such as MSCI, many studies have shown that fuels with characteristics intermediate between gasoline and diesel fuel are necessary. Many researchers have shown, however, that existing industry metrics such as Octane Number and Cetane Number are insufficient to represent fuel ignition characteristics for advanced engine combustion modes. In light of the poor performance of traditional metrics, new methods have been proposed to try and better characterize, order, and rank fuels used in HCCI operation. However, studies have since shown that when a broad array of fuels are considered, these recent metrics fail to adequately define a characteristic HCCI fuel index. Described in this work is an analysis of fuel reactivity in traditional and advanced internal combustion engines. Firstly, conventional engine regimes are broken down to their basic components, providing a framework for investigating the context of fuel reactivity. This analysis allows a novel equation to be formulated which links the historic metrics of Octane Number and Cetane Number. As part of this analysis a parameter, the knock length, is developed which explains the underlying principles of the Research and Motor Octane Number scales and further shows why some fuels test differently in these two methods. The knock length is also used to investigate unusual behavior observed in Methane Number reference fuels data - behavior which traditional concepts such as ignition delay and flame speed are unable to explain on their own. Secondly, this work focuses on the application of fuels such as bio-derived alcohols (ethanol and butanol) and fatty acid methyl esters in traditional and advanced combustion applications. Reactivity differences between alcohol and petroleum fuels are described and explained. Lastly, a new metric, the HCCI Number, is developed which allows the prediction of combustion timing in HCCI engines, and is highly amenable toward the development of bench-top laboratory apparatuses to facilitate practical adoption by fuel manufactures. Data from 23 different fuel blends tested in Cooperative Fuel Research (CFR) engines, a Fuel Ignition Tester, and a HCCI engine provide the experimental support for the theory presented herein. Additionally, a new chemical-kinetic mechanism is developed and used to describe combustion of n-butanol/n-heptane fuel mixtures in both conventional and advanced combustion… Advisors/Committee Members: Marchese, Anthony J. (advisor), Reardon, Ken (committee member), Olsen, Daniel (committee member), Gao, Xinfeng (committee member).

Subjects/Keywords: FIT; n-butanol; HCCI; fuel reactivity

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APA (6^th Edition):

Baumgardner, M. E. (2014). Characterizing fuel reactivity in advanced internal combustion engines. (Doctoral Dissertation). Colorado State University. Retrieved from http://hdl.handle.net/10217/82656

Chicago Manual of Style (16^th Edition):

Baumgardner, Marc E. “Characterizing fuel reactivity in advanced internal combustion engines.” 2014. Doctoral Dissertation, Colorado State University. Accessed March 05, 2021. http://hdl.handle.net/10217/82656.

MLA Handbook (7^th Edition):

Baumgardner, Marc E. “Characterizing fuel reactivity in advanced internal combustion engines.” 2014. Web. 05 Mar 2021.

Vancouver:

Baumgardner ME. Characterizing fuel reactivity in advanced internal combustion engines. [Internet] [Doctoral dissertation]. Colorado State University; 2014. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10217/82656.

Council of Science Editors:

Baumgardner ME. Characterizing fuel reactivity in advanced internal combustion engines. [Doctoral Dissertation]. Colorado State University; 2014. Available from: http://hdl.handle.net/10217/82656

Colorado State University

25. Bucy, Harrison. Oxidative stability and ignition quality of algae derived methyl esters containing varying levels of methyl eicosapentaenoate and methyl docosahexaenoate.

Degree: MS(M.S.), Mechanical Engineering, 2011, Colorado State University

URL: http://hdl.handle.net/10217/47253

► Microalgae is currently receiving strong consideration as a potential biofuel feedstock to help meet the advanced biofuels mandate of the 2007 Energy Independence and Security… (more)

▼ Microalgae is currently receiving strong consideration as a potential biofuel feedstock to help meet the advanced biofuels mandate of the 2007 Energy Independence and Security Act because of its theoretically high yield (gallons/acre/year) in comparison to current terrestrial feedstocks. Additionally, microalgae also do not compete with food and can be cultivated with wastewater on non-arable land. Microalgae lipids can be converted into a variety of biofuels including fatty acid methyl esters (e.g. FAME biodiesel), renewable diesel, renewable gasoline, or jet fuel. For microalgae derived FAME, the fuel properties will be directly related to the fatty acid composition of the lipids produced by the given microalgae strain. Several microalgae species under consideration for wide scale cultivation, such as Nannochloropsis, produce lipids with fatty acid compositions containing substantially higher quantities of long chain-polyunsaturated fatty acids (LC-PUFA) in comparison to terrestrial feedstocks. It is expected that increased levels of LC-PUFA will be problematic in terms of meeting all of the current ASTM specifications for biodiesel. For example, it is known that oxidative stability and cetane number decrease with increasing levels of LC-PUFA. However, these same LC-PUFA fatty acids, such as eicosapentaenoic acid (EPA: C20:5) and docosahexaenoic acid (DHA: C22:6) are known to have high nutritional value thereby making separation of these compounds economically attractive. Given the uncertainty in the future value of these LC-PUFA compounds and the economic viability of the separation process, the goal of this study was to examine the oxidative stability and ignition quality of algae-based FAME with varying levels of EPA and DHA removal. Oxidative stability tests were conducted at a temperature of 110 °C and airflow of 10 L/h using a Metrohm 743 Rancimat with automatic induction period determination following the EN 14112 Method from the ASTM D6751 and EN 14214 Standards, which call for induction periods of at least three hours and six hours, respectively. Derived Cetane Number testing was conducted using a Waukesha FIT following the ASTM D7170 Method. Tests were conducted with synthetic algal oil blends manufactured from various sources to match the fatty acid compositions of several algae strains subjected to varying removal amounts of roughly 0 - 100 percent LC-PUFA. In addition, tests were also conducted with real algal methyl esters produced from multiple sources. The bis-allylic position equivalent (BAPE) was calculated for each fuel sample to quantify the level of unsaturation. The induction period was then plotted as a function of BAPE, which showed that the oxidative stability varied exponentially with the amount of LC-PUFA. The results suggest that removal of 45 - 65 percent of the LC-PUFA from Nannochloropsis-based algal methyl esters would be sufficient for meeting existing ASTM specifications for oxidative stability and 75 - 85 percent removal would be needed to meet the EN specification. … Advisors/Committee Members: Marchese, Anthony John, 1967- (advisor), Willson, Bryan D. (committee member), Smith, T. Gordon (committee member).

Subjects/Keywords: algae; biodiesel; DHA; EPA; ignition quality; oxidative stability

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APA (6^th Edition):

Bucy, H. (2011). Oxidative stability and ignition quality of algae derived methyl esters containing varying levels of methyl eicosapentaenoate and methyl docosahexaenoate. (Masters Thesis). Colorado State University. Retrieved from http://hdl.handle.net/10217/47253

Chicago Manual of Style (16^th Edition):

Bucy, Harrison. “Oxidative stability and ignition quality of algae derived methyl esters containing varying levels of methyl eicosapentaenoate and methyl docosahexaenoate.” 2011. Masters Thesis, Colorado State University. Accessed March 05, 2021. http://hdl.handle.net/10217/47253.

MLA Handbook (7^th Edition):

Bucy, Harrison. “Oxidative stability and ignition quality of algae derived methyl esters containing varying levels of methyl eicosapentaenoate and methyl docosahexaenoate.” 2011. Web. 05 Mar 2021.

Vancouver:

Bucy H. Oxidative stability and ignition quality of algae derived methyl esters containing varying levels of methyl eicosapentaenoate and methyl docosahexaenoate. [Internet] [Masters thesis]. Colorado State University; 2011. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10217/47253.

Council of Science Editors:

Bucy H. Oxidative stability and ignition quality of algae derived methyl esters containing varying levels of methyl eicosapentaenoate and methyl docosahexaenoate. [Masters Thesis]. Colorado State University; 2011. Available from: http://hdl.handle.net/10217/47253

Colorado State University

26. Grumstrup, Torben. NOx formation in methyl ester, alcohol, and alkane droplet autoignition and combustion: PLIF measurements and detailed kinetic modeling.

Degree: PhD, Mechanical Engineering, 2014, Colorado State University

URL: http://hdl.handle.net/10217/83769

► Numerous studies have shown that diesel engines fueled by fatty-acid methyl ester biodiesel often exhibit slightly increased production of oxides of nitrogen (NOx) in comparison… (more)

▼ Numerous studies have shown that diesel engines fueled by fatty-acid methyl ester biodiesel often exhibit slightly increased production of oxides of nitrogen (NOx) in comparison to petroleum diesel. A number of explanations for this increase have been proposed. One theory, which has been supported by optical engine test results, suggests that the presence of oxygen atoms in the methyl ester fuel molecule results in a leaner premixed autoignition zone, thereby increasing in-cylinder temperatures and promoting Zel'dovich NOx production. Other experiments have suggested that the unsaturated methyl esters in biodiesel cause an increase in CH radical production (and/or other potential precursors such as C2O) which in turn increases Fenimore NOx formation. In this work, these hypotheses are explored experimentally and computationally by considering autoignition and combustion of single, isolated methyl ester, alcohol and alkane droplets. Experiments were conducted in which the planar laser-induced fluorescence (PLIF) spectroscopy technique was applied to burning liquid fuel droplets in free-fall. A monodisperse stream of droplets was generated by a piezoelectric device and passed through a resistively heated ignition coil. A pulsed laser beam from a Nd:YAG-pumped dye laser (10 Hz, 10 ns width) was formed into a sheet and passed through the droplet flame. The dye laser was tuned to excite hydroxyl (OH) at 282.9 nm and nitric oxide (NO) at 226.0 nm. The resulting fluorescence was imaged by a Cooke Corporation DiCam Pro ICCD digital camera. Band pass filters were utilized to reject laser light scattering while admitting fluorescence wavelengths. Due to the small fluorescence signal, many fluorescence images were averaged together to create a useful average image; approximately 250 and 1000 images were averaged for OH and NO spectroscopy, respectively. Finally, pixel intensity of the averaged fluorescence image was integrated about the droplet center to create qualitative radial profiles of OH and NO concentration. Profiles were generated for a number of oxygenated fuels and one pure hydrocarbon: methanol, ethanol, 1-propanol, methyl butanoate, methyl decanoate, and n-heptane. To quantitatively interpret the contribution of Zel'dovich and Fenimore NOx mechanisms on NOx formation in the vicinity of igniting liquid droplets, detailed numerical droplet combustion simulations were conducted. The transient, spherically symmetric droplet combustion modeling featured detailed gas-phase kinetics, spectrally resolved radiant heat transfer, and multicomponent gas transport. New chemical kinetic mechanisms were created by appending NOx chemical kinetics to existing detailed methanol, methyl butanoate, and n-heptane mechanisms. In the computations, non-oxygenated (heptane) and oxygenated (methyl butanoate, methanol) fuel droplets are introduced into a hot (1150 K) air ambient whereupon the liquid vaporizes, thus producing a stratified fuel/air mixture that thermally autoignites after an ignition delay period. The computational results… Advisors/Committee Members: Marchese, Anthony J. (advisor), Yalin, Azer (advisor), Kreidenweis, Sonia (committee member), Olsen, Daniel B. (committee member).

Subjects/Keywords: biodiesel; PLIF; droplet combustion

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Grumstrup, T. (2014). NOx formation in methyl ester, alcohol, and alkane droplet autoignition and combustion: PLIF measurements and detailed kinetic modeling. (Doctoral Dissertation). Colorado State University. Retrieved from http://hdl.handle.net/10217/83769

Chicago Manual of Style (16^th Edition):

Grumstrup, Torben. “NOx formation in methyl ester, alcohol, and alkane droplet autoignition and combustion: PLIF measurements and detailed kinetic modeling.” 2014. Doctoral Dissertation, Colorado State University. Accessed March 05, 2021. http://hdl.handle.net/10217/83769.

MLA Handbook (7^th Edition):

Grumstrup, Torben. “NOx formation in methyl ester, alcohol, and alkane droplet autoignition and combustion: PLIF measurements and detailed kinetic modeling.” 2014. Web. 05 Mar 2021.

Vancouver:

Grumstrup T. NOx formation in methyl ester, alcohol, and alkane droplet autoignition and combustion: PLIF measurements and detailed kinetic modeling. [Internet] [Doctoral dissertation]. Colorado State University; 2014. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10217/83769.

Council of Science Editors:

Grumstrup T. NOx formation in methyl ester, alcohol, and alkane droplet autoignition and combustion: PLIF measurements and detailed kinetic modeling. [Doctoral Dissertation]. Colorado State University; 2014. Available from: http://hdl.handle.net/10217/83769

Colorado State University

27. Grassian, David. Modelling and analysis of systems on offshore oil and gas platforms.

Degree: PhD, Systems Engineering, 2019, Colorado State University

URL: http://hdl.handle.net/10217/199767

► This research examines oil and gas systems from the seemingly underutilized perspective of energy; this is counterintuitive since the energy content of hydrocarbon products is… (more)

▼ This research examines oil and gas systems from the seemingly underutilized perspective of energy; this is counterintuitive since the energy content of hydrocarbon products is its most distinguishing characteristic and the very reason why it is valued by society. It is clear that the amount of energy required to extract crude oil is increasing over time, at the long-term global level, and at the much shorter time span of individual fields. The global trend is a well-documented phenomenon and is related to the depletion of the most energetically favorable reservoirs and a coincidental growing global demand for energy. Concerning existing fields, it is often necessary to implement increasingly higher energy intensity methods to extract the remaining crude oil resources. These trends are the impetus for the industry to gain a better understanding of the relationship between the application of energy and the production of crude oil across a wide spectrum of production methods. Reservoir management and petroleum engineering are highly evolved and scientifically rigorous disciplines, but their practices and methods tend to circumvent the single most important, value-added, quality of hydrocarbon extraction systems, the actual energy recovered, which is the difference between the energy extracted and the energy applied. Therefore, the motivation for this research is to outline existing energy evaluation methods which can be applied to oil extraction systems, illuminate the elements of these methods which can provide the greatest practical advantage to the oil and gas industry, and last, but certainly not least, to demonstrate the pivotal role of energy in crude oil extraction systems. As such, case studies are developed for three small offshore oilfields. The techniques applied include the identification of appropriate boundaries for the system, subsystems and equipment items, the calculation of energy related balances at each level, the development of energy related performance indicators, and lastly, analysis of performance. Indicators, such as the Energy Intensity (EI) and the Energy Return on Investment (EROI), are derived for different levels of the crude oil extraction systems. The dimensionless EROI is the energy returned divided by the energy invested, while the thermodynamic EI is essentially the inverse of the EROI, although alternative dimensional EIs may also be applied on a commodity or process basis. The case studies begin by developing long term time-series EROIs for three oil fields, with breakdowns that take into account the construction, drilling and operational phases of each field. The results corroborated the work of other researchers that indicated that the energy required to produce crude oil at the individual field level increases over time. The calculated EROIs drop steeply in all three fields as the crude oil production declines and the production of associated formation water increases. The increasing energy intensity of the production operations phase tends to dominate the long-term EROI… Advisors/Committee Members: Olsen, Daniel (advisor), Bradley, Thomas (committee member), Carlson, Kenneth (committee member), Marchese, Anthony (committee member).

Subjects/Keywords: energy; lifecycle analysis; recovery methods; hydrocarbons; electrical submersible pumps; oil and gas

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APA (6^th Edition):

Grassian, D. (2019). Modelling and analysis of systems on offshore oil and gas platforms. (Doctoral Dissertation). Colorado State University. Retrieved from http://hdl.handle.net/10217/199767

Chicago Manual of Style (16^th Edition):

Grassian, David. “Modelling and analysis of systems on offshore oil and gas platforms.” 2019. Doctoral Dissertation, Colorado State University. Accessed March 05, 2021. http://hdl.handle.net/10217/199767.

MLA Handbook (7^th Edition):

Grassian, David. “Modelling and analysis of systems on offshore oil and gas platforms.” 2019. Web. 05 Mar 2021.

Vancouver:

Grassian D. Modelling and analysis of systems on offshore oil and gas platforms. [Internet] [Doctoral dissertation]. Colorado State University; 2019. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10217/199767.

Council of Science Editors:

Grassian D. Modelling and analysis of systems on offshore oil and gas platforms. [Doctoral Dissertation]. Colorado State University; 2019. Available from: http://hdl.handle.net/10217/199767

Colorado State University

28. Thompson, Andrew T. Effect of altitude on turbocharger performance parameters for heavy duty diesel engines: experiments and GT-Power modeling, The.

Degree: MS(M.S.), Mechanical Engineering, 2014, Colorado State University

URL: http://hdl.handle.net/10217/82663

► Operation at high altitude increases the risk of high cycle fatigue (HCF) failure on turbine blades in internal combustion engine turbochargers. Because engine manufacturers rarely… (more)

▼ Operation at high altitude increases the risk of high cycle fatigue (HCF) failure on turbine blades in internal combustion engine turbochargers. Because engine manufacturers rarely acquire performance data at the high altitude limits of their engines, it is imperative that manufacturers rely on computer simulation to visualize, quantify and understand turbocharger performance when experimental tests are not practical. Typically, CFD and FEA models are used to predict HCF damage for turbine wheels. However, the boundary conditions and other input data required for such simulations are often unknown at high altitudes. The main objective of this thesis was to develop these critical boundary conditions and input data for a Cummins QSK19 CI engine and a Cummins QSK50 CI engine. This objective was accomplished by installing and testing both of these engines at 5000ft elevation and calibrating GT-Power computer simulation models against the experimental data at 5000ft elevation. After the models were calibrated against experimental data, the models were extrapolated to the altitude capability of these engines and the critical boundary conditions were recorded. In addition to the diesel engine experiments and modeling, a single cylinder HCCI computer simulation model was developed to evaluate the performance of Woschni and Hohenberg heat transfer correlations by comparing GT-Power model predictions with measured in-cylinder pressure data. Analysis was performed by generating a single zone GT-Power model of a modified John Deere DI 2.4L four-cylinder engine, which was previously converted at CSU to operate in HCCI port injection mode. The HCCI engine was operated at an equivalence ratio of 0.33 and a fuel mixture of 40% iso-octane and 60% n-heptane by volume. The combustion chemistry was modeled using a reduced Primary Reference Fuel (PRF) mechanism from Ra and Reitz with 41 species and 130 reactions. The Cummins modeling results indicate that GT-Power can predict turbocharger performance within 7.59% variation from measured data at 5000ft. When the model was extrapolated to 8000ft, GT-Power predicted an average expansion ratio increase of 1.81% and an average turbine inlet temperature decrease of 2% for the QSK19 CI engine. The Cummins QSK50 GT-Power model predicted an average expansion ratio increase of 2.73% and an average turbine inlet temperature decrease of 9.12% from 5000ft to 8000ft. The HCCI simulation results showed that GT-Power can accurately predict the start of combustion. In addition, the simulation results showed that the pressure rise rate has a low sensitivity to the in-cylinder heat transfer rate. Advisors/Committee Members: Marchese, Anthony J. (advisor), Olsen, Daniel (committee member), De Miranda, Micahel A. (committee member).

Subjects/Keywords: HCCI; altitude; engines; GT-Power; modeling; turbocharger

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Thompson, A. T. (2014). Effect of altitude on turbocharger performance parameters for heavy duty diesel engines: experiments and GT-Power modeling, The. (Masters Thesis). Colorado State University. Retrieved from http://hdl.handle.net/10217/82663

Chicago Manual of Style (16^th Edition):

Thompson, Andrew T. “Effect of altitude on turbocharger performance parameters for heavy duty diesel engines: experiments and GT-Power modeling, The.” 2014. Masters Thesis, Colorado State University. Accessed March 05, 2021. http://hdl.handle.net/10217/82663.

MLA Handbook (7^th Edition):

Thompson, Andrew T. “Effect of altitude on turbocharger performance parameters for heavy duty diesel engines: experiments and GT-Power modeling, The.” 2014. Web. 05 Mar 2021.

Vancouver:

Thompson AT. Effect of altitude on turbocharger performance parameters for heavy duty diesel engines: experiments and GT-Power modeling, The. [Internet] [Masters thesis]. Colorado State University; 2014. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10217/82663.

Council of Science Editors:

Thompson AT. Effect of altitude on turbocharger performance parameters for heavy duty diesel engines: experiments and GT-Power modeling, The. [Masters Thesis]. Colorado State University; 2014. Available from: http://hdl.handle.net/10217/82663

Colorado State University

29. Wood, Eric. Battery end-of-life considerations for plug-in hybrid electric vehicles.

Degree: MS(M.S.), Mechanical Engineering, 2011, Colorado State University

URL: http://hdl.handle.net/10217/70361

► Plug-in hybrid electric vehicles (PHEVs) represent an advanced vehicle technology with the potential to displace petroleum consumption with energy generated on the US electric grid.… (more)

▼ Plug-in hybrid electric vehicles (PHEVs) represent an advanced vehicle technology with the potential to displace petroleum consumption with energy generated on the US electric grid. While many benefits have been associated with the increased electrification of the US vehicle fleet, concerns over battery lifetime and replacement costs remain an obstacle to widespread PHEV adoption. In order to accurately determine the lifecycle cost of PHEVs, assessment studies must make use of informed assumptions regarding battery degradation and replacement. These assumptions should approach end-of-life (EOL) metrics not only in terms of pack level degradation but also loss of vehicle efficiency and performance in order to accurately represent consumer incentive for battery replacement. Battery degradation calculations should also remain sensitive to the range of ambient conditions and usage scenarios likely to be encountered in the US market. Degradation resulting from a single duty cycle has the potential to misrepresent battery life distributions for the US fleet. In this study, the sensitivity of PHEV lifecycle cost to the battery replacement assumption is explored to underscore the need for an improved understanding of PHEV battery EOL conditions. PHEV specific battery test results are presented to evaluate the ability of industry standard life test procedures to predict battery degradation in PHEVs. These test results are used as inputs to a vehicle simulation program to understand changes in efficiency and performance with respect to battery degradation using a light commercial vehicle simulated as a blended-mode capable, parallel PHEV20. A predictive battery degradation model based on empirical data is used to explore sensitivity of battery wear to various parameters including design variables, ambient conditions, and usage scenarios. A distribution of expected wear rates for a light-duty, midsize passenger vehicle modeled as a series PHEV35 is presented to highlight the uncertainty associated with battery life subject to US ambient conditions and driving distributions. The results of this study show that active management of PHEV battery degradation by the vehicle control system can improve PHEV performance and fuel consumption relative to a more passive baseline. Simulation of the PHEV20 throughout its battery lifetime shows that battery replacement will be neither economically incentivized nor necessary to maintain performance. The spectrum of climate and usage conditions PHEVs are expected to face in the US market suggest that the assumption of a single average ambient condition for battery wear calculations may not be representative of observed behavior in the fleet. These results have important implications for techno-economic evaluations of PHEVs which have treated battery replacement and its costs with inconsistency. Advisors/Committee Members: Bradley, Thomas H. (advisor), Marchese, Anthony J. (committee member), Young, Peter M. (committee member).

Subjects/Keywords: battery degradation; PHEV; lithium-ion

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Wood, E. (2011). Battery end-of-life considerations for plug-in hybrid electric vehicles. (Masters Thesis). Colorado State University. Retrieved from http://hdl.handle.net/10217/70361

Chicago Manual of Style (16^th Edition):

Wood, Eric. “Battery end-of-life considerations for plug-in hybrid electric vehicles.” 2011. Masters Thesis, Colorado State University. Accessed March 05, 2021. http://hdl.handle.net/10217/70361.

MLA Handbook (7^th Edition):

Wood, Eric. “Battery end-of-life considerations for plug-in hybrid electric vehicles.” 2011. Web. 05 Mar 2021.

Vancouver:

Wood E. Battery end-of-life considerations for plug-in hybrid electric vehicles. [Internet] [Masters thesis]. Colorado State University; 2011. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10217/70361.

Council of Science Editors:

Wood E. Battery end-of-life considerations for plug-in hybrid electric vehicles. [Masters Thesis]. Colorado State University; 2011. Available from: http://hdl.handle.net/10217/70361

Colorado State University

30. Lakshminarayanan, Arunachalam. Testing and performance measurement of straight vegetable oils as an alternative fuel for diesel engines.

Degree: MS(M.S.), Mechanical Engineering, 2014, Colorado State University

URL: http://hdl.handle.net/10217/88566

► Rising fuel prices, growing energy demand, concerns over domestic energy security and global warming from greenhouse gas emissions have triggered the global interest in bio-energy… (more)

▼ Rising fuel prices, growing energy demand, concerns over domestic energy security and global warming from greenhouse gas emissions have triggered the global interest in bio-energy and bio-fuel crop development. Backlash from these concerns can result in supply shocks of traditional fossil fuels and create immense economic pressure. It is thus widely argued that bio-fuels would particularly benefit developing countries by off-setting their dependencies on imported petroleum. Domestically, the transportation sector accounts for almost 40% of liquid fuel consumption, while on-farm application like tractors and combines for agricultural purposes uses close to an additional 18%. It is estimated that 40% of the farm budget can be attributed to the fuel costs. With the cost of diesel continuously rising, farmers are now looking at using Straight Vegetable Oil (SVO) as an alternative fuel by producing their own fuel crops. This study evaluates conventional diesel compared to the use of SVO like Camelina, Canola and Juncea grown on local farms in Colorado for their performance and emissions on a John Deere 4045 Tier-II engine. Additionally, physical properties like density and viscosity, metal/mineral content, and cold flow properties like CFPP and CP of these oils were measured using ASTM standards and compared to diesel. It was found that SVOs did not show significant differences compared to diesel fuel with regards to engine emissions, but did show an increase in thermal efficiency. Therefore, this study supports the continued development of SVO production as a viable alternative to diesel fuels, particularly for on-farm applications. The need for providing and developing a sustainable, economic and environmental friendly fuel alternative has taken an aggressive push which will require a strong multidisciplinary education in the field of bio-energy. Commercial bio-energy development has the potential to not only alleviate the energy concerns, but also to give renewed impetus to the agricultural sector and rural development. Advisors/Committee Members: Olsen, Daniel B. (advisor), Marchese, Anthony (committee member), Byrne, Patrick (committee member).

Subjects/Keywords: biofuels; emissions; engines; physical properties; straight vegetable oils; triglycerides

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Lakshminarayanan, A. (2014). Testing and performance measurement of straight vegetable oils as an alternative fuel for diesel engines. (Masters Thesis). Colorado State University. Retrieved from http://hdl.handle.net/10217/88566

Chicago Manual of Style (16^th Edition):

Lakshminarayanan, Arunachalam. “Testing and performance measurement of straight vegetable oils as an alternative fuel for diesel engines.” 2014. Masters Thesis, Colorado State University. Accessed March 05, 2021. http://hdl.handle.net/10217/88566.

MLA Handbook (7^th Edition):

Lakshminarayanan, Arunachalam. “Testing and performance measurement of straight vegetable oils as an alternative fuel for diesel engines.” 2014. Web. 05 Mar 2021.

Vancouver:

Lakshminarayanan A. Testing and performance measurement of straight vegetable oils as an alternative fuel for diesel engines. [Internet] [Masters thesis]. Colorado State University; 2014. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10217/88566.

Council of Science Editors:

Lakshminarayanan A. Testing and performance measurement of straight vegetable oils as an alternative fuel for diesel engines. [Masters Thesis]. Colorado State University; 2014. Available from: http://hdl.handle.net/10217/88566

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Open Access Theses and Dissertations