subject:(Microchannels)

Oregon State University

1. McNeff, Patrick Scot. Force Prediction in the Compression Sealing of an Ultra-thin Elastoviscoplastic Membrane.

Degree: MS, Industrial Engineering, 2016, Oregon State University

URL: http://hdl.handle.net/1957/58471

► The objective of this paper is to demonstrate a method for mechanically characterizing a 25 μm thick elastoviscoplastic hemodialysis membrane and for quantifying the force… (more)

Subjects/Keywords: microchannels; Microreactors

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APA (6^th Edition):

McNeff, P. S. (2016). Force Prediction in the Compression Sealing of an Ultra-thin Elastoviscoplastic Membrane. (Masters Thesis). Oregon State University. Retrieved from http://hdl.handle.net/1957/58471

Chicago Manual of Style (16^th Edition):

McNeff, Patrick Scot. “Force Prediction in the Compression Sealing of an Ultra-thin Elastoviscoplastic Membrane.” 2016. Masters Thesis, Oregon State University. Accessed March 05, 2021. http://hdl.handle.net/1957/58471.

MLA Handbook (7^th Edition):

McNeff, Patrick Scot. “Force Prediction in the Compression Sealing of an Ultra-thin Elastoviscoplastic Membrane.” 2016. Web. 05 Mar 2021.

Vancouver:

McNeff PS. Force Prediction in the Compression Sealing of an Ultra-thin Elastoviscoplastic Membrane. [Internet] [Masters thesis]. Oregon State University; 2016. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/1957/58471.

Council of Science Editors:

McNeff PS. Force Prediction in the Compression Sealing of an Ultra-thin Elastoviscoplastic Membrane. [Masters Thesis]. Oregon State University; 2016. Available from: http://hdl.handle.net/1957/58471

2. Pratte, William. Computational Modeling of a Diffusion Bonded Microchannel under High Pressure and Temperature.

Degree: MS, 2017, Oregon State University

URL: http://hdl.handle.net/1957/61373

► Diffusion bonded microchannels provide significant benefits by reducing space requirements while improving thermal efficiency when used in heat exchangers. In particular, these microchannels have potential… (more)

Subjects/Keywords: microchannels

…technology [1]. In such heat exchangers, microchannels take advantage of scaling laws to… …common methodology for manufacturing microchannels is diffusion bonding. In the diffusion… …230 provide desirable material properties for microchannels, such as high strength and… …Additional papers on modeling microchannels used for heat exchangers focus on residual stresses…

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APA (6^th Edition):

Pratte, W. (2017). Computational Modeling of a Diffusion Bonded Microchannel under High Pressure and Temperature. (Masters Thesis). Oregon State University. Retrieved from http://hdl.handle.net/1957/61373

Chicago Manual of Style (16^th Edition):

Pratte, William. “Computational Modeling of a Diffusion Bonded Microchannel under High Pressure and Temperature.” 2017. Masters Thesis, Oregon State University. Accessed March 05, 2021. http://hdl.handle.net/1957/61373.

MLA Handbook (7^th Edition):

Pratte, William. “Computational Modeling of a Diffusion Bonded Microchannel under High Pressure and Temperature.” 2017. Web. 05 Mar 2021.

Vancouver:

Pratte W. Computational Modeling of a Diffusion Bonded Microchannel under High Pressure and Temperature. [Internet] [Masters thesis]. Oregon State University; 2017. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/1957/61373.

Council of Science Editors:

Pratte W. Computational Modeling of a Diffusion Bonded Microchannel under High Pressure and Temperature. [Masters Thesis]. Oregon State University; 2017. Available from: http://hdl.handle.net/1957/61373

Louisiana State University

3. Dathathreya, Kavya. Characterization of Thermoplastic Fusion Bonding of Microchannels using Pressure Assisted Boiling Point Control System.

Degree: MS, Mechanical Engineering, 2016, Louisiana State University

URL: etd-11072016-164144 ; https://digitalcommons.lsu.edu/gradschool_theses/4537

► An innovative method of thermoplastic fusion bonding using a pressure assisted boiling point control (PABP) system was characterized to determine the optimum parameters for bonding… (more)

▼ An innovative method of thermoplastic fusion bonding using a pressure assisted boiling point control (PABP) system was characterized to determine the optimum parameters for bonding polymethyl methacrylate (PMMA) components containing microchannels and thin, 250 µm cover sheets. The PABP system enables precise control of the temperature boundary condition and the applied pressure by immersing the components being bonded in boiling water and varying the vapor pressure. Test structure geometries containing microchannels of two depths and four different aspect ratios were designed: 1:10 (Depth: 10µm, Width: 100 µm and Depth: 5µm, Width: 50 µm), 1:50 (Depth: 10µm, Width: 500µm and Depth: 5µm, Width: 250 µm), 1:100 (Depth: 10µm, Width: 1000µm and Depth: 5µm, Width: 500µm) and 1:200 (Depth: 10µm, Width: 2000µm and Depth: 5µm, Width: 1000µm). Microchannels were hot embossed using micro-milled brass mold inserts. Bonding conditions were optimized by observing microchannel deformation under a microscope. The quality of the bonded samples were rupture and leak tested to determine the integrity and strength of the bonds. Mean rupture pressures for channels of AR of 1:10, 1:50 and 1:100 were 851.02 kPa, 780.14 kPa and 706.09 kPa repectively for shallower channels and 831.93 kPa, 739.3 kPa and 524.38 kPa respectively for deeper channels bonded using open loop system. Rupture pressure decreased with decreasing AR and was higher for shallower channels. A closed loop control system was developed for the automatic temperature control. Results of bonding with both open loop and closed loop systems were compared. Mean rupture pressure for channels of AR 1:10, 1:50 and 1:100 for 5 µm depth were 977.54 kPa, 930.93 kPa and 751.39 kPa respectively and 912.11 kPa, 800.07 kPa and 550.96 kPa respectively for 10 µm depth. It was found that the rupture test results were more consistent and repeatable with closed loop system because of better control of the bonding temperature.

Subjects/Keywords: PMMA; microchannels; bonding

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APA (6^th Edition):

Dathathreya, K. (2016). Characterization of Thermoplastic Fusion Bonding of Microchannels using Pressure Assisted Boiling Point Control System. (Masters Thesis). Louisiana State University. Retrieved from etd-11072016-164144 ; https://digitalcommons.lsu.edu/gradschool_theses/4537

Chicago Manual of Style (16^th Edition):

Dathathreya, Kavya. “Characterization of Thermoplastic Fusion Bonding of Microchannels using Pressure Assisted Boiling Point Control System.” 2016. Masters Thesis, Louisiana State University. Accessed March 05, 2021. etd-11072016-164144 ; https://digitalcommons.lsu.edu/gradschool_theses/4537.

MLA Handbook (7^th Edition):

Dathathreya, Kavya. “Characterization of Thermoplastic Fusion Bonding of Microchannels using Pressure Assisted Boiling Point Control System.” 2016. Web. 05 Mar 2021.

Vancouver:

Dathathreya K. Characterization of Thermoplastic Fusion Bonding of Microchannels using Pressure Assisted Boiling Point Control System. [Internet] [Masters thesis]. Louisiana State University; 2016. [cited 2021 Mar 05]. Available from: etd-11072016-164144 ; https://digitalcommons.lsu.edu/gradschool_theses/4537.

Council of Science Editors:

Dathathreya K. Characterization of Thermoplastic Fusion Bonding of Microchannels using Pressure Assisted Boiling Point Control System. [Masters Thesis]. Louisiana State University; 2016. Available from: etd-11072016-164144 ; https://digitalcommons.lsu.edu/gradschool_theses/4537

University of Edinburgh

4. Korniliou, Sofia. Experimental study on local heat transfer coefficients and the effect of aspect ratio on flow boiling in a microchannel.

Degree: PhD, 2018, University of Edinburgh

URL: http://hdl.handle.net/1842/31080

► Flow boiling in integrated microchannel systems is a cooling technology that has received significant attention in recent years as an effective option for high heat… (more)

▼ Flow boiling in integrated microchannel systems is a cooling technology that has received significant attention in recent years as an effective option for high heat flux microelectronic devices as it provides high heat transfer and small variations in surface temperature. However, there are still a number of issues to be addressed before this technology is used for commercial applications. Amongst the issues that require further investigation are the two-phase heat transfer enhancement mechanisms, the effect of channel geometry on heat transfer characteristics, two-phase flow instabilities, critical heat flux and interfacial liquid-vapour heat transfer in the vicinity of the wall. This work is an experimental study on two-phase flow boiling in multi- and single-rectangular microchannels. Experimental research was performed on the effect of the channel aspect ratio and hydraulic diameter, particularly for parallel multi-microchannel systems in order to provide design guidelines. Flow boiling experiments were performed using deionised water in silicon microchannel heat sinks with width-to-depth aspect ratios (a) from 0.33 to 3 and hydraulic diameters from 50 μm to 150 μm. The effect of aspect ratio on two-phase flow boiling local heat transfer coefficient and two-phase pressure drop was investigated as well as the two-phase heat transfer coefficients trends with mass flux for the constant heat fluxes of 151 kW m-2, 183 kW m- 2, 271 kW m-2 and 363 kW m-2. Wall temperature measurements were obtained from five integrated thin nickel film temperature sensors. An integrated thin aluminium heater enabled uniform heating with a small thermal resistance between the heater and the channels. The microfabricated temperature sensors were used with simultaneous high-speed imaging and pressure measurements in order to obtain a better insight related to temperature and pressure fluctuations caused by two-phase flow instabilities under uniform heating in parallel microchannels. The results demonstrated that the aspect ratio of the microchannels affects flow boiling heat transfer coefficients. However, there is not clear trend of the aspect ratio on the heat transfer coefficient. Pressure drop was found to increase with increasing aspect ratio. Wide microchannels but not very shallow, with a = 1.5 and Dh = 120 μm, have shown good heat transfer performance, by producing modest two-phase pressure drop of maximum 200 mbar for the highest heat flux and heat transfer coefficients of 200 kW m-2 during two-phase flow boiling conditions. For the high aspect ratio, values of 2 and 3 two-phase flow boiling heat transfer coefficients were measured to be lower compared to aspect ratio of 1.5. Microchannels with aspect ratios higher than 1.5 produced severe wall temperature fluctuations for high heat fluxes that periodically reached extreme wall temperature values in excess of 250 ˚C. The consequences of these severe wall temperature and pressure fluctuations at high aspect ratios of 2 and 3 resulted in non-uniform flow distribution and temporal…

Subjects/Keywords: 660; flow boiling; microchannels

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APA (6^th Edition):

Korniliou, S. (2018). Experimental study on local heat transfer coefficients and the effect of aspect ratio on flow boiling in a microchannel. (Doctoral Dissertation). University of Edinburgh. Retrieved from http://hdl.handle.net/1842/31080

Chicago Manual of Style (16^th Edition):

Korniliou, Sofia. “Experimental study on local heat transfer coefficients and the effect of aspect ratio on flow boiling in a microchannel.” 2018. Doctoral Dissertation, University of Edinburgh. Accessed March 05, 2021. http://hdl.handle.net/1842/31080.

MLA Handbook (7^th Edition):

Korniliou, Sofia. “Experimental study on local heat transfer coefficients and the effect of aspect ratio on flow boiling in a microchannel.” 2018. Web. 05 Mar 2021.

Vancouver:

Korniliou S. Experimental study on local heat transfer coefficients and the effect of aspect ratio on flow boiling in a microchannel. [Internet] [Doctoral dissertation]. University of Edinburgh; 2018. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/1842/31080.

Council of Science Editors:

Korniliou S. Experimental study on local heat transfer coefficients and the effect of aspect ratio on flow boiling in a microchannel. [Doctoral Dissertation]. University of Edinburgh; 2018. Available from: http://hdl.handle.net/1842/31080

Georgia Tech

5. Keniar, Khoudor. ANALYTICAL MODELING OF CONDENSATION IN MICROCHANNELS WITH EXPERIMENTAL VALIDATION.

Degree: PhD, Mechanical Engineering, 2020, Georgia Tech

URL: http://hdl.handle.net/1853/62790

► The condenser is a critical component in many energy intensive systems, such as HVAC, power plants, automobiles, and gas liquefaction plants. Microchannel geometries offer the… (more)

▼ The condenser is a critical component in many energy intensive systems, such as HVAC, power plants, automobiles, and gas liquefaction plants. Microchannel geometries offer the potential for more efficient and compact configurations for condensers. Condensation in small hydraulic diameter channels yields high heat transfer coefficients, combined with larger surface area-to-volume ratios, leading to increased system-level efficiency. Internal convective condensation in microchannels typically occurs in annular and intermittent flow regimes. This study develops mechanistic models for these two regimes, validated through relevant experiments. A first principles model for laminar annular flow condensation is developed. It addresses some of the limitations of models found in the literature, which are mostly shape-specific or have assumptions that are not valid over broad ranges of geometries. The present model is developed for an arbitrary channel geometry. For intermittent flow, most of the models in the literature address the hydrodynamics, or at best, heat transfer without phase change, while others are highly empirical. Therefore, a framework for a mechanistic model of condensation in intermittent flow in microchannels is developed here. A transient Lagrangian bubble-tracking scheme is used. Experimental data are collected using synthetic refrigerants as working fluids on a test facility capable of measuring heat transfer at low mass fluxes. Data are collected using two microchannel shapes, square and circle with hydraulic diameters of 0.98 mm and 1.55 mm, respectively. The tests are conducted at different saturation temperatures, saturation-to-wall temperature differences, and a range of low mass fluxes. These results show reasonable agreement with the predictions of mechanistic models for annular and intermittent flows. The effects of operating conditions and channel geometry on condensation are discussed and interpreted based on the underlying flow mechanisms. Advisors/Committee Members: Garimella, Srinivas (advisor), Ghiaasiaan, S. Mostafa (committee member), Genzale, Caroline (committee member), Fuller, Thomas (committee member), Kumar, Satish (committee member).

Subjects/Keywords: Condensation; Microchannels; Analytical Model; Experiments

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APA (6^th Edition):

Keniar, K. (2020). ANALYTICAL MODELING OF CONDENSATION IN MICROCHANNELS WITH EXPERIMENTAL VALIDATION. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/62790

Chicago Manual of Style (16^th Edition):

Keniar, Khoudor. “ANALYTICAL MODELING OF CONDENSATION IN MICROCHANNELS WITH EXPERIMENTAL VALIDATION.” 2020. Doctoral Dissertation, Georgia Tech. Accessed March 05, 2021. http://hdl.handle.net/1853/62790.

MLA Handbook (7^th Edition):

Keniar, Khoudor. “ANALYTICAL MODELING OF CONDENSATION IN MICROCHANNELS WITH EXPERIMENTAL VALIDATION.” 2020. Web. 05 Mar 2021.

Vancouver:

Keniar K. ANALYTICAL MODELING OF CONDENSATION IN MICROCHANNELS WITH EXPERIMENTAL VALIDATION. [Internet] [Doctoral dissertation]. Georgia Tech; 2020. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/1853/62790.

Council of Science Editors:

Keniar K. ANALYTICAL MODELING OF CONDENSATION IN MICROCHANNELS WITH EXPERIMENTAL VALIDATION. [Doctoral Dissertation]. Georgia Tech; 2020. Available from: http://hdl.handle.net/1853/62790

Georgia Tech

6. Jakaboski, Blake Elaine. Forced Convection in Microchannels with Nanostructures on One Wall.

Degree: MS, Mechanical Engineering, 2004, Georgia Tech

URL: http://hdl.handle.net/1853/4984

► New electronic devices are faster than ever before, incorporate a higher level of integration, and as a result, need to dissipate higher heat fluxes. Active… (more)

Subjects/Keywords: Microchannels; Nanostructures

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APA (6^th Edition):

Jakaboski, B. E. (2004). Forced Convection in Microchannels with Nanostructures on One Wall. (Masters Thesis). Georgia Tech. Retrieved from http://hdl.handle.net/1853/4984

Chicago Manual of Style (16^th Edition):

Jakaboski, Blake Elaine. “Forced Convection in Microchannels with Nanostructures on One Wall.” 2004. Masters Thesis, Georgia Tech. Accessed March 05, 2021. http://hdl.handle.net/1853/4984.

MLA Handbook (7^th Edition):

Jakaboski, Blake Elaine. “Forced Convection in Microchannels with Nanostructures on One Wall.” 2004. Web. 05 Mar 2021.

Vancouver:

Jakaboski BE. Forced Convection in Microchannels with Nanostructures on One Wall. [Internet] [Masters thesis]. Georgia Tech; 2004. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/1853/4984.

Council of Science Editors:

Jakaboski BE. Forced Convection in Microchannels with Nanostructures on One Wall. [Masters Thesis]. Georgia Tech; 2004. Available from: http://hdl.handle.net/1853/4984

University of Waterloo

7. Galvis, Elmer. Single-Phase and Boiling Flow in Microchannels with High Heat Flux.

Degree: 2012, University of Waterloo

URL: http://hdl.handle.net/10012/7155

► A cooling system for high heat flux applications is examined using microchannel evaporators with water as the working fluid and boiling as the heat transfer… (more)

▼ A cooling system for high heat flux applications is examined using microchannel evaporators with water as the working fluid and boiling as the heat transfer mechanism. Experimental studies are performed using single channel microevaporators allowing for better control of the flow mechanics unlike other investigations where multiple, parallel, flow channels can result in a non-uniform distribution of the working fluid. High-speed flow visualizations are performed in conjunction with heat transfer and pressure drop measurements to support the quantitative experimental data. Flow patterns associated with a range of boundary conditions are characterized and then presented in the form of novel flow regime maps that intrinsically reflect the physical mechanisms controlling two-phase pressure distributions and heat transfer behavior. Given the complexity associated with modeling of boiling heat transfer and the lack of a universal model that provides accurate predictions across a broad spectrum of flow conditions, flow regime maps serve as a valuable modeling aid to assist in targeted modeling over specific flow regimes. This work represents a novel and original contribution to the understanding of boiling mechanisms for water in microchannels. The flow patterns in this work are found to be closely coupled with mass flux, heat flux, and channel size; where re-wetting and pressure oscillations play a crucial role, and are likely responsible for its development and evolution. Reversed flow, typically attributed to a non-uniform fluid distribution in multiple channel microevaporators by other researchers, is shown to be a result of the upstream expansion of confined bubbles. During flow boiling, the pressure drop in the microchannel increases with the heat flux for a constant flow rate due to the significant acceleration effects associated with smaller channels, unlike in single-phase flow where the pressure drop is constant. Water flow boiling in rectangular microchannels, although not extensively explored in the published literature, provides an extremely high cooling capacity, with dissipation rates approaching 440 W/cm², making this an ideal candidate for cooling of next generation electronic systems. Single-phase flow studies revealed that pressure and heat transfer coefficient macroscale models are transferable to microchannels with hydraulic diameters down to 200 µm, when the entrance effects and minor losses are properly considered. These studies include laminar developing flow conditions not commonly considered in the literature and fully developed flow. Since the applicability of macroscale theories to microchannels is often questioned, this investigation helps clarify this issue for microchannels within the range of experimental conditions explored in this work. Finally, new correlations for the hydrodynamic entrance length are proposed for rectangular microchannels and good agreement is found when compared with published experimental data over a wide range of Reynolds number. These correlations are…

Subjects/Keywords: Microchannels; Boiling; Single phase

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APA (6^th Edition):

Galvis, E. (2012). Single-Phase and Boiling Flow in Microchannels with High Heat Flux. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/7155

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Galvis, Elmer. “Single-Phase and Boiling Flow in Microchannels with High Heat Flux.” 2012. Thesis, University of Waterloo. Accessed March 05, 2021. http://hdl.handle.net/10012/7155.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Galvis, Elmer. “Single-Phase and Boiling Flow in Microchannels with High Heat Flux.” 2012. Web. 05 Mar 2021.

Vancouver:

Galvis E. Single-Phase and Boiling Flow in Microchannels with High Heat Flux. [Internet] [Thesis]. University of Waterloo; 2012. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10012/7155.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Galvis E. Single-Phase and Boiling Flow in Microchannels with High Heat Flux. [Thesis]. University of Waterloo; 2012. Available from: http://hdl.handle.net/10012/7155

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Rochester Institute of Technology

8. McLaughlin, Callum. Directional Notches as Microstructures to Promote Nucleation and Heat Transfer in Pool Boiling.

Degree: MS, Mechanical Engineering, 2019, Rochester Institute of Technology

URL: https://scholarworks.rit.edu/theses/10235

► Heat generation in electronic hardware has become a major limiting factor in achieving maximum efficiency in modern computer parts. Classically forced flow convection systems… (more)

▼ Heat generation in electronic hardware has become a major limiting factor in achieving maximum efficiency in modern computer parts. Classically forced flow convection systems are used to remove this heat at high rates but can be costly to implement and can take up space that may be needed for other critical components. In response to this, systems that use fewer parts scale in compact spaces are needed. In these situations, pool boiling as a heat transfer mechanism can excel. Pool boiling removes heat through the evaporation of fluid. On a flat surface pool boiling is chaotic and this random nature may hinder its ability to remove heat as effectively. The surface geometry of a pool boiling system can be altered to direct the flow of generated vapor bubbles to allow for increased heat flow and higher heat transfer performance. By creating paths for the vapor to follow we can induce currents in the flow of cool fluid to the heater surface, creating a faster cycle of vapor production therefore cooling the heated surface at a faster rate. The purpose of this study is to investigate angled chip notches as an alternative to already existing high heat transfer surfaces in pool boiling. These alternative chips may prove cheaper or easier to produce the alternative which may incorporate fine, hard to produce features or post process coatings like sintering and the addition of hydrophobic materials. This study will examine the effect these specifically designed notches have on the interaction between the directed vapor and the liquid pathways they create. By creating notches in the surface of the chip, vapor bubble is given sites to nucleate and form vapor pathways. The angle walls on the one side of the notch will act as a wedge when water being driven toward the notch pushes the nucleating bubble up and out of the notch. Combined with pairing nucleating notches up with another oppositely facing one the vapor bubble is departing earlier then it would have had it not been assisted by these surface elements. With just these paired notches placed in row, an HTC improvement of 158% was recorded, compared to a plain copper surface. With the inclusion of microchannels this improvement was brought up to 161% Advisors/Committee Members: Satish G. Kandlikar.

Subjects/Keywords: Liquid vapor pathways; Microchannels; Pool boiling

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APA (6^th Edition):

McLaughlin, C. (2019). Directional Notches as Microstructures to Promote Nucleation and Heat Transfer in Pool Boiling. (Masters Thesis). Rochester Institute of Technology. Retrieved from https://scholarworks.rit.edu/theses/10235

Chicago Manual of Style (16^th Edition):

McLaughlin, Callum. “Directional Notches as Microstructures to Promote Nucleation and Heat Transfer in Pool Boiling.” 2019. Masters Thesis, Rochester Institute of Technology. Accessed March 05, 2021. https://scholarworks.rit.edu/theses/10235.

MLA Handbook (7^th Edition):

McLaughlin, Callum. “Directional Notches as Microstructures to Promote Nucleation and Heat Transfer in Pool Boiling.” 2019. Web. 05 Mar 2021.

Vancouver:

McLaughlin C. Directional Notches as Microstructures to Promote Nucleation and Heat Transfer in Pool Boiling. [Internet] [Masters thesis]. Rochester Institute of Technology; 2019. [cited 2021 Mar 05]. Available from: https://scholarworks.rit.edu/theses/10235.

Council of Science Editors:

McLaughlin C. Directional Notches as Microstructures to Promote Nucleation and Heat Transfer in Pool Boiling. [Masters Thesis]. Rochester Institute of Technology; 2019. Available from: https://scholarworks.rit.edu/theses/10235

Rochester Institute of Technology

9. Recinella, Alyssa. Enhanced Flow Boiling Heat Transfer in Radial Microchannel and Offset Strip Fin Geometries.

Degree: MS, Mechanical Engineering, 2016, Rochester Institute of Technology

URL: https://scholarworks.rit.edu/theses/9310

► Devices used for various electronic purposes are increasing in power consumption and performance. Due to this growth, the amount of heat dissipated over a… (more)

▼ Devices used for various electronic purposes are increasing in power consumption and performance. Due to this growth, the amount of heat dissipated over a small surface area has proportionally continued to increase. Despite previous efforts involving single phase natural and forced convection, these methods are no longer effective in high heat removal. Research in two-phase liquid cooling has become more prominent. Boiling has the potential to yield large critical heat flux values, high heat transfer coefficients and lower pressure drops. Many different surface enhancements and working fluids have been tested to increase efficiency and minimize heat losses. Flow boiling in microchannels have been widely explored in literature for high heat flux dissipation. Microchannels are compact and subsequently easy to manufacture. However, due to flow instabilities that accompany microchannels, different configurations and additional modifications have been explored in order to maximize performance. In this work, a radial geometry is experimentally investigated with a flow inlet over the center of the chip. This central inlet creates a reduction in flow length and therefore a reduction in pressure drop and flow instabilities. Two testing surfaces were explored including a radial microchannel array and a radial offset strip fin array. To maximize performance even further, a gap has been added between the cover plate and testing surface to increase flow area and reduce pressure drop. One significant observation shows that an increase in flow rate mitigates the instabilities seen in the channels and prolongs critical heat flux (CHF). Due to these phenomena, all configurations are tested in the modified configuration with higher flow rates ranging from 120-320 mL/min. Radial microchannels with an added gap yielded maximum performance values of 385.5 W/cm² at 42.7°C wall superheat with a high pressure drop of about 140 kPa while the offset strip fin configuration achieved much higher heat transfer performance with CHF values exceeding 900 W/cm² at 58.6°C wall superheat. The offset strip fin geometry shows significant performance enhancements compared to the microchannels. For both the gap geometries and the closed geometries, the offset values are much higher than the radial microchannels. Advisors/Committee Members: Satish G. Kandlikar.

Subjects/Keywords: Flow boiling; Heat transfer; Microchannels; Radial

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APA (6^th Edition):

Recinella, A. (2016). Enhanced Flow Boiling Heat Transfer in Radial Microchannel and Offset Strip Fin Geometries. (Masters Thesis). Rochester Institute of Technology. Retrieved from https://scholarworks.rit.edu/theses/9310

Chicago Manual of Style (16^th Edition):

Recinella, Alyssa. “Enhanced Flow Boiling Heat Transfer in Radial Microchannel and Offset Strip Fin Geometries.” 2016. Masters Thesis, Rochester Institute of Technology. Accessed March 05, 2021. https://scholarworks.rit.edu/theses/9310.

MLA Handbook (7^th Edition):

Recinella, Alyssa. “Enhanced Flow Boiling Heat Transfer in Radial Microchannel and Offset Strip Fin Geometries.” 2016. Web. 05 Mar 2021.

Vancouver:

Recinella A. Enhanced Flow Boiling Heat Transfer in Radial Microchannel and Offset Strip Fin Geometries. [Internet] [Masters thesis]. Rochester Institute of Technology; 2016. [cited 2021 Mar 05]. Available from: https://scholarworks.rit.edu/theses/9310.

Council of Science Editors:

Recinella A. Enhanced Flow Boiling Heat Transfer in Radial Microchannel and Offset Strip Fin Geometries. [Masters Thesis]. Rochester Institute of Technology; 2016. Available from: https://scholarworks.rit.edu/theses/9310

Texas A&M University

10. Berestovskyi, Dmytro V. Surface Finish Modeling in Micromilling of Biocompatible Materials.

Degree: MS, Mechanical Engineering, 2013, Texas A&M University

URL: http://hdl.handle.net/1969.1/151023

► Over the last few decades, miniaturization of the product became a necessity for many industries to achieve successful technological development, satisfy customer needs, and stay… (more)

▼ Over the last few decades, miniaturization of the product became a necessity for many industries to achieve successful technological development, satisfy customer needs, and stay economically competitive in the market. Thus, many medical, aerospace, and electronic devices tend to decrease in size. Along with the strong demand for miniaturization, new cutting-edge micromanufacturing techniques are developing in order to produce microcomponents with a smooth surface finish and high dimensional accuracy. In the medical industry, some devices require manufacturing of fluidic microchannels on biocompatible materials for transportation of exact amount of medicine to a defined location. Often such microchannels must be manufactured to achieve a high aspect ratio, a submicron surface finish, and an anisotropic controlled profile. The fabrication of such channels on biocompatible materials still poses a challenge. This study developed micromanufacturing technique to produce the microchannels and satisfy all the requirements listed above. Computer controlled micromilling on a high speed machine system in minimum quantity lubrication was used to remove most materials and define a channel pattern. Microchannels were machined with ball end mills of diameters from Ø152μm to Ø198μm on NiTi alloy, 304 and 316L stainless steels. Assessment of microchannel was performed with optical microscopy, scanning electron microscopy, and white light interferometry. The theoretical surface roughness in ball end milling was derived using geometrical approach. The theoretical surface finish model was compared and validated with the experimental surface finish data. Meso- and macro-scale milling confirmed the validity of the model, but surface finish in micro-scale milling was measured to be a few orders of magnitude higher due to size effect and build-up edge. The build-up-edge was reduced when using AlTiN coated tools and milling in minimum quantity lubrication. The empirical surface roughness model obtained in this study shows the dependence of surface finish on chip load in micromilling. In order to further enhance the surface finish of milled microchannels additional finishing technique was identified. A separate study developed an effective electrochemical polishing technique to remove burrs and enhance surface finish of milled microchannels. When applying to 304, 316L stainless steel alloys and NiTi alloy, this hybrid technique can repeatedly produce microchannels with an average surface finish less than 100nm. Advisors/Committee Members: Hung, Wayne Nguyen (advisor), Suh, Chii-Der (committee member), Wang, Jyhwen (committee member).

Subjects/Keywords: micromilling; microchannels; surface finish; biocompatible materials

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APA (6^th Edition):

Berestovskyi, D. V. (2013). Surface Finish Modeling in Micromilling of Biocompatible Materials. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/151023

Chicago Manual of Style (16^th Edition):

Berestovskyi, Dmytro V. “Surface Finish Modeling in Micromilling of Biocompatible Materials.” 2013. Masters Thesis, Texas A&M University. Accessed March 05, 2021. http://hdl.handle.net/1969.1/151023.

MLA Handbook (7^th Edition):

Berestovskyi, Dmytro V. “Surface Finish Modeling in Micromilling of Biocompatible Materials.” 2013. Web. 05 Mar 2021.

Vancouver:

Berestovskyi DV. Surface Finish Modeling in Micromilling of Biocompatible Materials. [Internet] [Masters thesis]. Texas A&M University; 2013. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/1969.1/151023.

Council of Science Editors:

Berestovskyi DV. Surface Finish Modeling in Micromilling of Biocompatible Materials. [Masters Thesis]. Texas A&M University; 2013. Available from: http://hdl.handle.net/1969.1/151023

University of Houston

11. Samel, Gauri 1988-. DEVELOPMENT OF SELF-ALIGNED INTERDIGITATED ELECTRODES WITHIN A MICROFLUIDIC CHANNEL FOR AN ELECTROCHEMILUMINESCENCE SENSOR.

Degree: MSin Electrical Engineering, Electrical Engineering, 2012, University of Houston

URL: http://hdl.handle.net/10657/815

► The aim of this work was to develop a fabrication sequence for forming microchannels with integrated, interdigitated electrodes using only one lithographic step as a… (more)

Subjects/Keywords: Microchannels; SU-8; Biosensors; Electrical engineering

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APA (6^th Edition):

Samel, G. 1. (2012). DEVELOPMENT OF SELF-ALIGNED INTERDIGITATED ELECTRODES WITHIN A MICROFLUIDIC CHANNEL FOR AN ELECTROCHEMILUMINESCENCE SENSOR. (Masters Thesis). University of Houston. Retrieved from http://hdl.handle.net/10657/815

Chicago Manual of Style (16^th Edition):

Samel, Gauri 1988-. “DEVELOPMENT OF SELF-ALIGNED INTERDIGITATED ELECTRODES WITHIN A MICROFLUIDIC CHANNEL FOR AN ELECTROCHEMILUMINESCENCE SENSOR.” 2012. Masters Thesis, University of Houston. Accessed March 05, 2021. http://hdl.handle.net/10657/815.

MLA Handbook (7^th Edition):

Samel, Gauri 1988-. “DEVELOPMENT OF SELF-ALIGNED INTERDIGITATED ELECTRODES WITHIN A MICROFLUIDIC CHANNEL FOR AN ELECTROCHEMILUMINESCENCE SENSOR.” 2012. Web. 05 Mar 2021.

Vancouver:

Samel G1. DEVELOPMENT OF SELF-ALIGNED INTERDIGITATED ELECTRODES WITHIN A MICROFLUIDIC CHANNEL FOR AN ELECTROCHEMILUMINESCENCE SENSOR. [Internet] [Masters thesis]. University of Houston; 2012. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10657/815.

Council of Science Editors:

Samel G1. DEVELOPMENT OF SELF-ALIGNED INTERDIGITATED ELECTRODES WITHIN A MICROFLUIDIC CHANNEL FOR AN ELECTROCHEMILUMINESCENCE SENSOR. [Masters Thesis]. University of Houston; 2012. Available from: http://hdl.handle.net/10657/815

University of Minnesota

12. Waikar, Ameya. Flow Boiling of A Dilute Emulsion In the Transition Regime.

Degree: M.S.M.E., Mechanical Engineering, 2020, University of Minnesota

URL: http://hdl.handle.net/11299/216096

► This investigation investigates heat transfer of water and flow boiling of dilute emulsion in transition and turbulent regime. The gap heights for microgap of 500… (more)

▼ This investigation investigates heat transfer of water and flow boiling of dilute emulsion in transition and turbulent regime. The gap heights for microgap of 500 and 1000 μm and nominal Reynolds number of 1600 and 2800. The emulsion in this study is an oil-in-water emulsions, where FC-72 is the oil whose droplets are suspended in water. The volume fractions for the emulsions are 1% and 2%. The heated test section is smooth. For single phase experiments, the heat transfer coefficient of water with increasing Reynolds number and decreasing the hydraulic diameter. The Nusselt number in the single-phase region is correlated to the Reynolds number, Prandtl number and aspect ratio of the channel. The Nusselt number varies linearly with ????????????ℎ.????????.????ℎ???? . In emulsion heat transfer on the smooth surfaces, the value of the heat transfer coefficient increases only for a volume fraction of 2% of the disperse component under certain conditions. Reducing the concentration to 1% provides no additional benefit and decreases heat transfer coefficient for all gap sizes and Reynolds number. The 2% emulsion has a larger overall heat transfer coefficient than that in water for lower hydraulic diameter and higher Reynolds number. The heat transfer coefficient increases with increasing wall temperature and plateaus at higher wall temperatures. The interaction between turbulence and boiling is also an area of interest in this investigation. When the emulsion boils, there is enhanced mixing in the flow, also leading to further agitation of the flow causing more turbulence. There is significant increase in pressure drop for the 2% emulsion with increasing wall temperature. Based on these observations and the previously suggested heat transfer mechanism, the following mechanisms are posited: conduction in thin film of FC-72 which reduces the heat transfer due to lower conductivity of FC-72; enhanced mixing due to boiling of FC-72 which increases heat transfer; and the boiling further increases the turbulence, enhancing the convection of the flow. These effects are quantified by correlations developed by using seven different non-dimensional parameters, and an empirical correlation is derived for calculating the heat transfer coefficient for the emulsion. The correlation is a good fit with 93.8% of data lying within ±30% of the predicted values. Further conclusions about the mechanisms involved in the flow boiling of emulsions have been made, and the data set for the flow boiling of emulsions has been further expanded into transitional and turbulent regimes.

Subjects/Keywords: Emulsion; Flow Boiling; Microchannels and microgap; Turbulence

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

APA (6^th Edition):

Waikar, A. (2020). Flow Boiling of A Dilute Emulsion In the Transition Regime. (Masters Thesis). University of Minnesota. Retrieved from http://hdl.handle.net/11299/216096

Chicago Manual of Style (16^th Edition):

Waikar, Ameya. “Flow Boiling of A Dilute Emulsion In the Transition Regime.” 2020. Masters Thesis, University of Minnesota. Accessed March 05, 2021. http://hdl.handle.net/11299/216096.

MLA Handbook (7^th Edition):

Waikar, Ameya. “Flow Boiling of A Dilute Emulsion In the Transition Regime.” 2020. Web. 05 Mar 2021.

Vancouver:

Waikar A. Flow Boiling of A Dilute Emulsion In the Transition Regime. [Internet] [Masters thesis]. University of Minnesota; 2020. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/11299/216096.

Council of Science Editors:

Waikar A. Flow Boiling of A Dilute Emulsion In the Transition Regime. [Masters Thesis]. University of Minnesota; 2020. Available from: http://hdl.handle.net/11299/216096

University of Manchester

13. Bautista Figueroa, Ulises. Mixing Enhancement in Microfluidic devices.

Degree: 2017, University of Manchester

URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:310935

► Microscale mixing is paramount for processing targeted drug delivery, chemical production and medical diagnostics. Mixing is often performed in a micromixer, which is a microfluidic… (more)

▼ Microscale mixing is paramount for processing targeted drug delivery, chemical production and medical diagnostics. Mixing is often performed in a micromixer, which is a microfluidic device where the fluids are confined in micro sized channels in the order of 100-500 Î¼m. Micromixing has many advantages over its macroscale counterpart, which include small sample consumption, portability, low cost, handling of dangerous materials, compact size and disposability. However, there are also many challenges for mixing enhancement that include low diffusivity rates, high surface-volume ratio, laminar flow, viscous effects, fluid confinement and surface defects are all significant challenges. This aim of this study is to design an effective and efficient micromixer that overcomes these limitations. The literature review summarises the different approaches that have been reported to address these technical challenges, which included numerous sub-processes and micromixer designs. The most common technique involved forcing the liquid samples to mix through a complex microchannel pattern. However, this approach was limited by the high-pressure drop, complex manufacturing of the microchannel, cleaning difficulties and long mixing distances. Other mixing techniques made use of external energy sources such as sound waves, electromagnetic fields, pulsing the flow inlets, temperature gradients, in an attempt to enhance mixing. Although some were effective in specific cases, they did not offer a broad solution for many applications. In order to address these issues, three novel micromixer designs were investigated and validated using a combination of numerical simulations and experiments; these included: 1) a micromixer with a modified geometry and synthetic jets, 2) a micromixer that exploited the multiphase flow principle and 3) a micromixer with a straight channel and a spinning disk. The results confirmed that it was not feasible to develop a micromixer by scaling down a macromixer. However, by modifying the geometry and adding synthetic jets, it was possible to achieve the desired mixing degree of 90% in just 3 seconds at 350 Î¼m downstream with a stroke length of 10.5 (Î”pp=263 Î¼m), Strouhal number of 0.525 (f=6 Hz) and Reynolds number of 0.25. However, the final design suffered technical issues and became complex. The second proposed solution relied on the multiphase flow principle that did not require a complex channel pattern, any external energy source or moving parts to effectively enhance mixing. A mixing quality of 95% was achieved within 0.2 seconds at 350 Î¼m downstream with typical Re<1. Conversely, this design suffered poor mixing performance at Re>2, which was addressed by incorporating a straight channel and spinning disk that achieved a mixing quality of 90% for any Re<10 at a spinning frequency of 15 Hz. The promising results obtained with the multiphase principle and spinning disk make them serious candidates for being implemented in practical applications. Advisors/Committee Members: KENNAUGH, ANDREW A, Dupere, Iain, Kennaugh, Andrew.

Subjects/Keywords: mixing; microchannels; synthetic jets; multiphase flow

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

APA (6^th Edition):

Bautista Figueroa, U. (2017). Mixing Enhancement in Microfluidic devices. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:310935

Chicago Manual of Style (16^th Edition):

Bautista Figueroa, Ulises. “Mixing Enhancement in Microfluidic devices.” 2017. Doctoral Dissertation, University of Manchester. Accessed March 05, 2021. http://www.manchester.ac.uk/escholar/uk-ac-man-scw:310935.

MLA Handbook (7^th Edition):

Bautista Figueroa, Ulises. “Mixing Enhancement in Microfluidic devices.” 2017. Web. 05 Mar 2021.

Vancouver:

Bautista Figueroa U. Mixing Enhancement in Microfluidic devices. [Internet] [Doctoral dissertation]. University of Manchester; 2017. [cited 2021 Mar 05]. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:310935.

Council of Science Editors:

Bautista Figueroa U. Mixing Enhancement in Microfluidic devices. [Doctoral Dissertation]. University of Manchester; 2017. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:310935

University of Manchester

14. Bautista Figueroa, Ulises. Mixing enhancement in microfluidic devices.

Degree: PhD, 2017, University of Manchester

URL: https://www.research.manchester.ac.uk/portal/en/theses/mixing-enhancement-in-microfluidic-devices(1412e6fe-c7e4-4a8b-af9e-50daf7b5ff1b).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.822895

► Microscale mixing is paramount for processing targeted drug delivery, chemical production and medical diagnostics. Mixing is often performed in a micromixer, which is a microfluidic… (more)

▼ Microscale mixing is paramount for processing targeted drug delivery, chemical production and medical diagnostics. Mixing is often performed in a micromixer, which is a microfluidic device where the fluids are confined in micro sized channels in the order of 100-500 Î1⁄4m. Micromixing has many advantages over its macroscale counterpart, which include small sample consumption, portability, low cost, handling of dangerous materials, compact size and disposability. However, there are also many challenges for mixing enhancement that include low diffusivity rates, high surface-volume ratio, laminar flow, viscous effects, fluid confinement and surface defects are all significant challenges. This aim of this study is to design an effective and efficient micromixer that overcomes these limitations. The literature review summarises the different approaches that have been reported to address these technical challenges, which included numerous sub-processes and micromixer designs. The most common technique involved forcing the liquid samples to mix through a complex microchannel pattern. However, this approach was limited by the high-pressure drop, complex manufacturing of the microchannel, cleaning difficulties and long mixing distances. Other mixing techniques made use of external energy sources such as sound waves, electromagnetic fields, pulsing the flow inlets, temperature gradients, in an attempt to enhance mixing. Although some were effective in specific cases, they did not offer a broad solution for many applications. In order to address these issues, three novel micromixer designs were investigated and validated using a combination of numerical simulations and experiments; these included: 1) a micromixer with a modified geometry and synthetic jets, 2) a micromixer that exploited the multiphase flow principle and 3) a micromixer with a straight channel and a spinning disk. The results confirmed that it was not feasible to develop a micromixer by scaling down a macromixer. However, by modifying the geometry and adding synthetic jets, it was possible to achieve the desired mixing degree of 90% in just 3 seconds at 350 μm downstream with a stroke length of 10.5 (Δpp=263 μm), Strouhal number of 0.525 (f=6 Hz) and Reynolds number of 0.25. However, the final design suffered technical issues and became complex. The second proposed solution relied on the multiphase flow principle that did not require a complex channel pattern, any external energy source or moving parts to effectively enhance mixing. A mixing quality of 95% was achieved within 0.2 seconds at 350 μm downstream with typical Re < 1. Conversely, this design suffered poor mixing performance at Re > 2, which was addressed by incorporating a straight channel and spinning disk that achieved a mixing quality of 90% for any Re < 10 at a spinning frequency of 15 Hz. The promising results obtained with the multiphase principle and spinning disk make them serious candidates for being implemented in practical applications.

Subjects/Keywords: mixing; microchannels; synthetic jets; multiphase flow

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

APA (6^th Edition):

Bautista Figueroa, U. (2017). Mixing enhancement in microfluidic devices. (Doctoral Dissertation). University of Manchester. Retrieved from https://www.research.manchester.ac.uk/portal/en/theses/mixing-enhancement-in-microfluidic-devices(1412e6fe-c7e4-4a8b-af9e-50daf7b5ff1b).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.822895

Chicago Manual of Style (16^th Edition):

Bautista Figueroa, Ulises. “Mixing enhancement in microfluidic devices.” 2017. Doctoral Dissertation, University of Manchester. Accessed March 05, 2021. https://www.research.manchester.ac.uk/portal/en/theses/mixing-enhancement-in-microfluidic-devices(1412e6fe-c7e4-4a8b-af9e-50daf7b5ff1b).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.822895.

MLA Handbook (7^th Edition):

Bautista Figueroa, Ulises. “Mixing enhancement in microfluidic devices.” 2017. Web. 05 Mar 2021.

Vancouver:

Bautista Figueroa U. Mixing enhancement in microfluidic devices. [Internet] [Doctoral dissertation]. University of Manchester; 2017. [cited 2021 Mar 05]. Available from: https://www.research.manchester.ac.uk/portal/en/theses/mixing-enhancement-in-microfluidic-devices(1412e6fe-c7e4-4a8b-af9e-50daf7b5ff1b).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.822895.

Council of Science Editors:

Bautista Figueroa U. Mixing enhancement in microfluidic devices. [Doctoral Dissertation]. University of Manchester; 2017. Available from: https://www.research.manchester.ac.uk/portal/en/theses/mixing-enhancement-in-microfluidic-devices(1412e6fe-c7e4-4a8b-af9e-50daf7b5ff1b).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.822895

Rochester Institute of Technology

15. Bapat, Akhilesh V. Experimental and numerical evaluation of single phase adiabatic flows in plain and enhanced microchannels.

Degree: Mechanical Engineering, 2007, Rochester Institute of Technology

URL: https://scholarworks.rit.edu/theses/5938

► Thermal Dissipation is a critical issue in the performance of semiconductor devices. The current practice is to use forced convection by air over a heat… (more)

▼ Thermal Dissipation is a critical issue in the performance of semiconductor devices. The current practice is to use forced convection by air over a heat sink which is bonded to the microelectronic device. With increased packing density of the circuits inside a chip, large amounts of heat is generated and air cooling is no longer sufficient. Forced liquid convection using microchannels is considered to be a viable option for cooling of these microprocessor chips. This work deals with the evaluation of the single phase pressure drop in microchannels. There are two types of microchannels under consideration. Plain microchannels which have basically long uninterrupted flow channels while the enhanced channels which have the interrupted flow lengths. Enhanced microchannels, because of their offset strip fin geometry, significantly increase both the heat transfer as well as the pressure drop. This work deals with the evaluation of single phase flow pressure drop in both plain and enhanced microchannels. For plain microchannels there have been a few investigations in the literature which suggest that the microchannel performance can generally be predicted using the classical fluid flow equations. However there are some experiments that still show departure from the classical theory that cannot be explained. It is proposed in this work that the reason for this discrepancy can be traced to the effects due to flow maldistribution in plain microchannels. A systematic experimental investigation is performed to study the effects of slight variations in channel dimensions and their influence on the flow maldistribution in an attempt to validate the applicability of classical theory to microchannel flows. Enhanced microchannels however have not been investigated thoroughly. There is very few data available in the literature. FLUENT is a CFD software which can be used as a tool to design and optimize these enhanced channels. However it has to be first validated with experiments. Thus pressure drop experiments are carried out on an offset strip fin silicon microchannel and the data is predicted using FLUENT, which is CFD software. Also existing predictive models for friction factor in offset strip fin minichannels are tested to check their validity for microchannel flows. For plain microchannels, it seen that with uniform flow assumption, the friction factor is either underpredicted or overpredicted using the theory depending upon the reference channel dimension. However by accounting flow maldistribution in plain microchannels, friction factor can be accurately determined using theoretical equations. For enhanced microchannels it is observed that FLUENT can predict the pressure drop within 10%. In this work only adiabatic flows are considered. It is recommended that this work should be extended to flows with heat transfer. Advisors/Committee Members: Kozak, Jeffrey.

Subjects/Keywords: Enhanced microchannels; Fluid flow equations; Microchannels; Thermal dissipation

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APA (6^th Edition):

Bapat, A. V. (2007). Experimental and numerical evaluation of single phase adiabatic flows in plain and enhanced microchannels. (Thesis). Rochester Institute of Technology. Retrieved from https://scholarworks.rit.edu/theses/5938

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Bapat, Akhilesh V. “Experimental and numerical evaluation of single phase adiabatic flows in plain and enhanced microchannels.” 2007. Thesis, Rochester Institute of Technology. Accessed March 05, 2021. https://scholarworks.rit.edu/theses/5938.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Bapat, Akhilesh V. “Experimental and numerical evaluation of single phase adiabatic flows in plain and enhanced microchannels.” 2007. Web. 05 Mar 2021.

Vancouver:

Bapat AV. Experimental and numerical evaluation of single phase adiabatic flows in plain and enhanced microchannels. [Internet] [Thesis]. Rochester Institute of Technology; 2007. [cited 2021 Mar 05]. Available from: https://scholarworks.rit.edu/theses/5938.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Bapat AV. Experimental and numerical evaluation of single phase adiabatic flows in plain and enhanced microchannels. [Thesis]. Rochester Institute of Technology; 2007. Available from: https://scholarworks.rit.edu/theses/5938

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Texas – Austin

16. Shah, Neil Pankaj, 1986-. COMSOL modeling of end effects in superhydrophobic microchannels for frictional reduction.

Degree: MSin Engineering, Mechanical Engineering, 2010, University of Texas – Austin

URL: http://hdl.handle.net/2152/ETD-UT-2010-08-1787

► This paper investigates the role of end-effects in superhydrophobic microchannels for frictional reduction through COMSOL based modeling. Two precursor derivations, the Kim & Hidrovo and… (more)

Subjects/Keywords: COMSOL; Microchannels; Superhydrophobic microchannels; Frictional reduction; Numerical models

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APA (6^th Edition):

Shah, Neil Pankaj, 1. (2010). COMSOL modeling of end effects in superhydrophobic microchannels for frictional reduction. (Masters Thesis). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/ETD-UT-2010-08-1787

Chicago Manual of Style (16^th Edition):

Shah, Neil Pankaj, 1986-. “COMSOL modeling of end effects in superhydrophobic microchannels for frictional reduction.” 2010. Masters Thesis, University of Texas – Austin. Accessed March 05, 2021. http://hdl.handle.net/2152/ETD-UT-2010-08-1787.

MLA Handbook (7^th Edition):

Shah, Neil Pankaj, 1986-. “COMSOL modeling of end effects in superhydrophobic microchannels for frictional reduction.” 2010. Web. 05 Mar 2021.

Vancouver:

Shah, Neil Pankaj 1. COMSOL modeling of end effects in superhydrophobic microchannels for frictional reduction. [Internet] [Masters thesis]. University of Texas – Austin; 2010. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/2152/ETD-UT-2010-08-1787.

Council of Science Editors:

Shah, Neil Pankaj 1. COMSOL modeling of end effects in superhydrophobic microchannels for frictional reduction. [Masters Thesis]. University of Texas – Austin; 2010. Available from: http://hdl.handle.net/2152/ETD-UT-2010-08-1787

Rochester Institute of Technology

17. Cooke, Dwight. Experimental study of pool boiling heat transfer enhancement over microchanneled surfaces.

Degree: Mechanical Engineering, 2011, Rochester Institute of Technology

URL: https://scholarworks.rit.edu/theses/5894

► Pool boiling is of interest in heat transfer applications because of its potential for removing large amount of heat resulting from the latent heat of… (more)

▼ Pool boiling is of interest in heat transfer applications because of its potential for removing large amount of heat resulting from the latent heat of evaporation and little pressure drop penalty for circulating coolant through the system. However, the heat transfer performance of pool boiling systems is still not comparable to the cooling ability provided by enhanced microchannels operating under single-phase conditions. This investigation focuses on the bubble dynamics and heat transfer on plain and structured microchanneled surfaces under various heat fluxes in an effort to understand the underlying heat transfer mechanism through the use of a high speed camera. In a preliminary study, silicon chips have been tested in the nucleate boiling regime, and beneficial microchannel geometries have been identified. It is determined that heat transfer enhancement occurs because of (i) an increase in surface area and (ii) an improvement in the heat transfer mechanism through the channels functioning as liquid conduits for three side heating. The range for channel size in which the greatest enhancement occurs has been identified as being 200 - 400 µm width and 300 - 500 µm depth. The second study has been investigated with copper chips, with improvements to the test setup for accurate measurement of surface temperature. Ten chips, in addition to a plain chip have been evaluated for heat transfer performance. It has been determined that surfaces with many, small hydraulic diameter channels enhance the heat transfer as well as surfaces with wide and deep channels. The best performing chip had a record heat transfer coefficient of 269 kW/m2K. The large heat fluxes of over 240 W/cm2 were attained without reaching the critical heat flux condition, because of the open channels on the surface acting as conduits for liquid supply to the nucleation sites. The microchannels prevent surface dryout and critical heat flux (CHF), while the channel width controls the size of the departing bubbles. Advisors/Committee Members: Kandlikar, Satish.

Subjects/Keywords: Bubble dynamics; Grooves; Heat transfer enhancement; Microchannels; Pool boiling

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

APA (6^th Edition):

Cooke, D. (2011). Experimental study of pool boiling heat transfer enhancement over microchanneled surfaces. (Thesis). Rochester Institute of Technology. Retrieved from https://scholarworks.rit.edu/theses/5894

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Cooke, Dwight. “Experimental study of pool boiling heat transfer enhancement over microchanneled surfaces.” 2011. Thesis, Rochester Institute of Technology. Accessed March 05, 2021. https://scholarworks.rit.edu/theses/5894.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Cooke, Dwight. “Experimental study of pool boiling heat transfer enhancement over microchanneled surfaces.” 2011. Web. 05 Mar 2021.

Vancouver:

Cooke D. Experimental study of pool boiling heat transfer enhancement over microchanneled surfaces. [Internet] [Thesis]. Rochester Institute of Technology; 2011. [cited 2021 Mar 05]. Available from: https://scholarworks.rit.edu/theses/5894.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Cooke D. Experimental study of pool boiling heat transfer enhancement over microchanneled surfaces. [Thesis]. Rochester Institute of Technology; 2011. Available from: https://scholarworks.rit.edu/theses/5894

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

18. Cabral, Francismara Pires. Estudo da ebulição convectiva de nanofluidos no interior de microcanais.

Degree: Mestrado, Térmica e Fluidos, 2012, University of São Paulo

URL: http://www.teses.usp.br/teses/disponiveis/18/18147/tde-16092013-163829/ ;

►

Este trabalho trata do estudo teórico do ebulição convectiva de nanofluidos em canais de diâmetro reduzido (denominados de microcanais). Ele aborda, primeiramente, uma análise da… (more)

▼

Este trabalho trata do estudo teórico do ebulição convectiva de nanofluidos em canais de diâmetro reduzido (denominados de microcanais). Ele aborda, primeiramente, uma análise da literatura sobre a ebulição convectiva de fluidos convencionais em microcanais, na qual são discutidos critérios para a transição entre macro e microcanais e os padrões de escoamentos observados em canais de reduzido diâmetro. Métodos para a previsão das propriedades de transporte de nanofluidos foram levantados da literatura e estudos experimentais da convecção forçada, da ebulição nucleada e da ebulição convectiva de nanofluidos foram discutidos. Um método para a previsão do coeficiente de transferência de calor de nanofluidos em microcanais durante a ebulição convectiva foi proposto baseado em modelos convencionais da literatura ajustados para nanofluidos. O ajuste dos modelos convencionais foi realizado através de análise regressiva de dados experimentais para ebulição nucleada e convecção forçada de nanofluidos levantados da literatura, e da análise crítica de adimensionais que capturassem a influência das nanopartículas no processo de transferência de calor. De maneira geral o método proposto neste estudo apresenta concordância razoável com dados experimentais independentes, referente ao acréscimo do coeficiente de transferência de calor com o incremento da concentração volumétrica de nanopartículas. No entanto, a escassez de estudos experimentais sobre a ebulição convectiva de nanofluidos, especialmente em microcanais, impossibilitou uma análise mais aprofundada do método proposto.

The present work aims the theoretical study of convective boiling of nanofluids in small diameter channels (called microchannel). It discusses an analysis of the literature on convective boiling of conventional fluids in microchannels which presents criteria for the transition between conventional and microchannels and the flow patterns observed in small diameter channels. Methods for predicting the transport properties of nanofluids were compiled from the literature and experimental studies of forced convection, nucleate boiling and convective boiling of nanofluids were discussed. A method for predicting the heat transfer coefficient of nanofluids in microchannels during convective boiling was proposed based on conventional models from literature adjusted to nanofluids. The conventional models fitting was performed by regression analysis of experimental data for nucleate boiling and forced convection of nanofluids compiled from the literature and by critical analysis of dimensionless numbers which enable to capture the influence of nanoparticles on heat transfer process. In general the proposed method in this work presents reasonable agreement with independent experimental data regarding the increase in heat transfer coefficient with increasing nanoparticles volume fraction. However the scarcity of experimental studies on the convective boiling of nanofluids, especially in microchannels, precluded further analysis of the proposed method.

Advisors/Committee Members: Ribatski, Gherhardt.

Subjects/Keywords: Ebulição convectiva; Flow boiling; Microcanais; Microchannels; Nanofluidos; Nanofluids

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APA (6^th Edition):

Cabral, F. P. (2012). Estudo da ebulição convectiva de nanofluidos no interior de microcanais. (Masters Thesis). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/18/18147/tde-16092013-163829/ ;

Chicago Manual of Style (16^th Edition):

Cabral, Francismara Pires. “Estudo da ebulição convectiva de nanofluidos no interior de microcanais.” 2012. Masters Thesis, University of São Paulo. Accessed March 05, 2021. http://www.teses.usp.br/teses/disponiveis/18/18147/tde-16092013-163829/ ;.

MLA Handbook (7^th Edition):

Cabral, Francismara Pires. “Estudo da ebulição convectiva de nanofluidos no interior de microcanais.” 2012. Web. 05 Mar 2021.

Vancouver:

Cabral FP. Estudo da ebulição convectiva de nanofluidos no interior de microcanais. [Internet] [Masters thesis]. University of São Paulo; 2012. [cited 2021 Mar 05]. Available from: http://www.teses.usp.br/teses/disponiveis/18/18147/tde-16092013-163829/ ;.

Council of Science Editors:

Cabral FP. Estudo da ebulição convectiva de nanofluidos no interior de microcanais. [Masters Thesis]. University of São Paulo; 2012. Available from: http://www.teses.usp.br/teses/disponiveis/18/18147/tde-16092013-163829/ ;

University of Ottawa

19. Gerson, Eleanor. Promoting Endothelial Cell Growth within Microchannels - Modification of Polydimethylsiloxane and Microfabrication of Circular Microchannels .

Degree: 2018, University of Ottawa

URL: http://hdl.handle.net/10393/37555

► Polydimethylsiloxane (PDMS) microfluidic channels, fabricated using low cost and simple soft lithography methods, conventionally have rectangular cross-sections. Despite being often used for organs-on-a-chip and cardiovascular… (more)

▼ Polydimethylsiloxane (PDMS) microfluidic channels, fabricated using low cost and simple soft lithography methods, conventionally have rectangular cross-sections. Despite being often used for organs-on-a-chip and cardiovascular research, these devices do not mimic the circular cross-sections of blood vessels in the human body, creating potential inaccuracies in observed flow conditions and cell behaviours. The purpose of this thesis is to (i) compare and optimize fabrication techniques for microchannels with circular cross-sections, (ii) assess biocompatibility of different surface functionalization approaches for Human Umbilical Vein Endothelial Cell (HUVEC) adhesion and growth, (iii) culture HUVECs within circular microchannels to mimic blood vessel features, and (iv) compare gene expression of HUVECs cultured in 3D circular microchannels to those cultured on 2D surfaces. We show that wire molding is superior to the gas stream technique for producing circular cross-section microchannels with high aspect ratios, circularity, and channel geometry precision. Fibronectin (FN) and polydopamine (PD) surface coatings on PDMS, as well as alternative collagen substrates, were tested for biocompatibility with HUVECs in 2D cultures; fibronectin coated PDMS (PDMS-FN) substrates facilitated cell attachment, spreading and growth. We demonstrate the capability of growing HUVECs on the inner surface of circular PDMS microchannels created using the wire-mold method and treated with fibronectin. A syringe pump was used to induce shear stress on the HUVECs grown in circular microchannels. Relative to static growth conditions, longer cell culture growth periods were more feasible under flow and altered cell morphology was observed. Finally, Microarray analysis revealed significantly different gene expression profiles for HUVECs cultured within PDMS-FN circular cross-section microchannels as compared to HUVECs cultured on PDMS-FN in a 2D environment, thereby highlighting the critical importance of in vitro conditions for mimicking the in vivo reality.

Subjects/Keywords: Microfluidics; Microchannels; Seeding of endothelial cells; Microfabrication; Flow; Circular cross-section

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APA (6^th Edition):

Gerson, E. (2018). Promoting Endothelial Cell Growth within Microchannels - Modification of Polydimethylsiloxane and Microfabrication of Circular Microchannels . (Thesis). University of Ottawa. Retrieved from http://hdl.handle.net/10393/37555

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Gerson, Eleanor. “Promoting Endothelial Cell Growth within Microchannels - Modification of Polydimethylsiloxane and Microfabrication of Circular Microchannels .” 2018. Thesis, University of Ottawa. Accessed March 05, 2021. http://hdl.handle.net/10393/37555.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Gerson, Eleanor. “Promoting Endothelial Cell Growth within Microchannels - Modification of Polydimethylsiloxane and Microfabrication of Circular Microchannels .” 2018. Web. 05 Mar 2021.

Vancouver:

Gerson E. Promoting Endothelial Cell Growth within Microchannels - Modification of Polydimethylsiloxane and Microfabrication of Circular Microchannels . [Internet] [Thesis]. University of Ottawa; 2018. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10393/37555.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Gerson E. Promoting Endothelial Cell Growth within Microchannels - Modification of Polydimethylsiloxane and Microfabrication of Circular Microchannels . [Thesis]. University of Ottawa; 2018. Available from: http://hdl.handle.net/10393/37555

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Pretoria

20. Adewumi, Olayinka Omowunmi. Constructal design and optimisation of combined microchannels and micro pin fins for microelectronic cooling.

Degree: PhD, Mechanical and Aeronautical Engineering, 2016, University of Pretoria

URL: http://hdl.handle.net/2263/61305

► Microchannels and micro pin fins have been employed for almost four decades in the cooling of microelectronic devices and research is still being done in… (more)

▼ Microchannels and micro pin fins have been employed for almost four decades in the cooling of microelectronic devices and research is still being done in this field to improve the thermal performance of these micro heat sinks. In this research, the constructal design and computational fluid dynamics code was used with a goal-driven optimisation tool to numerically investigate the thermal performance of a novel design of combining microchannels and micro pin fins for microelectronic cooling applications. Existing designs of microchannels were first optimised and thereafter, three to seven rows of micro pin fins were inserted into the microchannels to investigate whether there was further improvement in thermal performance. The microchannels and micro pin fins were both embedded in a highly conductive solid substrate. three-dimensional geometric structure of the combined micro heat sink was optimised to achieve the objective of maximised thermal conductance, which is also minimised thermal resistance under various design conditions. The micro heat sinks investigated in the study were the single microchannel, two-layered microchannels with parallel and counter flow configurations, three-layered microchannels with parallel and counter flow configurations, the single microchannel with circular-, square- and hexagonal-shaped micro pin-fin inserts and the two-layered microchannels with circular-shaped micro pin-fin inserts. A numerical computational fluid dynamics (CFD) package with a goal-driven optimisation tool, which employs the finite-volume method, was used to analyse the fluid flow and heat transfer in the micro heat sinks investigated in this work. The thermal performances of all the micro heat sinks were compared for different application scenarios. Furthermore, the temperature variation on the heated base of the solid substrate was studied for the different micro heat sinks to investigate which of the heat sink designs minimised the temperature rise on the heated base best. This is very important in microelectronic cooling applications because temperature rise affects the reliability of the device. The heat sink design that best maximised thermal conductance and minimised temperature rise on the heated base was chosen as the best for microelectronic cooling. For all the cases considered, fixed volume constraints and manufacturing constraints were applied to ensure real-life applicability. It was concluded that optimal heat sink design for different application scenarios could be obtained speedily when a CFD package which had an optimisation tool was used. Advisors/Committee Members: Bello-Ochende, Tunde (advisor), Meyer, Josua P. (coadvisor).

Subjects/Keywords: UCTD; Microchannels; Thermal conductance; Thermal resistance; Temperature variation

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APA (6^th Edition):

Adewumi, O. (2016). Constructal design and optimisation of combined microchannels and micro pin fins for microelectronic cooling. (Doctoral Dissertation). University of Pretoria. Retrieved from http://hdl.handle.net/2263/61305

Chicago Manual of Style (16^th Edition):

Adewumi, Olayinka. “Constructal design and optimisation of combined microchannels and micro pin fins for microelectronic cooling.” 2016. Doctoral Dissertation, University of Pretoria. Accessed March 05, 2021. http://hdl.handle.net/2263/61305.

MLA Handbook (7^th Edition):

Adewumi, Olayinka. “Constructal design and optimisation of combined microchannels and micro pin fins for microelectronic cooling.” 2016. Web. 05 Mar 2021.

Vancouver:

Adewumi O. Constructal design and optimisation of combined microchannels and micro pin fins for microelectronic cooling. [Internet] [Doctoral dissertation]. University of Pretoria; 2016. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/2263/61305.

Council of Science Editors:

Adewumi O. Constructal design and optimisation of combined microchannels and micro pin fins for microelectronic cooling. [Doctoral Dissertation]. University of Pretoria; 2016. Available from: http://hdl.handle.net/2263/61305

Deakin University

21. Ghandoori, Tahir. Fabrication of polymeric microchannels with focused and defocused CO2 lasers.

Degree: 2014, Deakin University

URL: http://hdl.handle.net/10536/DRO/DU:30079687

► The control of energy distribution or energy intensity inside a laser spot using a defocusing method enables the formation of high-quality microchannels of multiple cross-sections… (more)

Subjects/Keywords: laser spot; defocusing method; high-quality microchannels; channel topology prediction

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APA (6^th Edition):

Ghandoori, T. (2014). Fabrication of polymeric microchannels with focused and defocused CO2 lasers. (Thesis). Deakin University. Retrieved from http://hdl.handle.net/10536/DRO/DU:30079687

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Ghandoori, Tahir. “Fabrication of polymeric microchannels with focused and defocused CO2 lasers.” 2014. Thesis, Deakin University. Accessed March 05, 2021. http://hdl.handle.net/10536/DRO/DU:30079687.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Ghandoori, Tahir. “Fabrication of polymeric microchannels with focused and defocused CO2 lasers.” 2014. Web. 05 Mar 2021.

Vancouver:

Ghandoori T. Fabrication of polymeric microchannels with focused and defocused CO2 lasers. [Internet] [Thesis]. Deakin University; 2014. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10536/DRO/DU:30079687.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Ghandoori T. Fabrication of polymeric microchannels with focused and defocused CO2 lasers. [Thesis]. Deakin University; 2014. Available from: http://hdl.handle.net/10536/DRO/DU:30079687

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Brno University of Technology

22. Hudeček, Ondřej. Laminace nízkoteplotní keramiky: The lamination of Low Temperature Co-fired Ceramic.

Degree: 2019, Brno University of Technology

URL: http://hdl.handle.net/11012/4894

► Master’s thesis deals with the optimalization of low-temperature cofired ceramic lamination process that affects the final quality of 3D structures (eg., channels, cavities, membranes, etc.).… (more)

Subjects/Keywords: LTCC; mikrokanálky; laminace; defekty; chlazení.; LTCC; microchannels; lamination; defects; cooling.

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APA (6^th Edition):

Hudeček, O. (2019). Laminace nízkoteplotní keramiky: The lamination of Low Temperature Co-fired Ceramic. (Thesis). Brno University of Technology. Retrieved from http://hdl.handle.net/11012/4894

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Hudeček, Ondřej. “Laminace nízkoteplotní keramiky: The lamination of Low Temperature Co-fired Ceramic.” 2019. Thesis, Brno University of Technology. Accessed March 05, 2021. http://hdl.handle.net/11012/4894.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Hudeček, Ondřej. “Laminace nízkoteplotní keramiky: The lamination of Low Temperature Co-fired Ceramic.” 2019. Web. 05 Mar 2021.

Vancouver:

Hudeček O. Laminace nízkoteplotní keramiky: The lamination of Low Temperature Co-fired Ceramic. [Internet] [Thesis]. Brno University of Technology; 2019. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/11012/4894.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Hudeček O. Laminace nízkoteplotní keramiky: The lamination of Low Temperature Co-fired Ceramic. [Thesis]. Brno University of Technology; 2019. Available from: http://hdl.handle.net/11012/4894

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Georgia Tech

23. Dietz, Carter Reynolds. Single-phase forced convection in a microchannel with carbon nanotubes for electronic cooling applications.

Degree: MS, Mechanical Engineering, 2007, Georgia Tech

URL: http://hdl.handle.net/1853/16133

► A comparative study was conducted to determine whether it would be advantageous to grow carbon nanotubes on the bottom surface of anisotropically-etched silicon microchannels to… (more)

Subjects/Keywords: Microchannels; Carbon nanotubes; Electronics cooling

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APA (6^th Edition):

Dietz, C. R. (2007). Single-phase forced convection in a microchannel with carbon nanotubes for electronic cooling applications. (Masters Thesis). Georgia Tech. Retrieved from http://hdl.handle.net/1853/16133

Chicago Manual of Style (16^th Edition):

Dietz, Carter Reynolds. “Single-phase forced convection in a microchannel with carbon nanotubes for electronic cooling applications.” 2007. Masters Thesis, Georgia Tech. Accessed March 05, 2021. http://hdl.handle.net/1853/16133.

MLA Handbook (7^th Edition):

Dietz, Carter Reynolds. “Single-phase forced convection in a microchannel with carbon nanotubes for electronic cooling applications.” 2007. Web. 05 Mar 2021.

Vancouver:

Dietz CR. Single-phase forced convection in a microchannel with carbon nanotubes for electronic cooling applications. [Internet] [Masters thesis]. Georgia Tech; 2007. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/1853/16133.

Council of Science Editors:

Dietz CR. Single-phase forced convection in a microchannel with carbon nanotubes for electronic cooling applications. [Masters Thesis]. Georgia Tech; 2007. Available from: http://hdl.handle.net/1853/16133

Georgia Tech

24. Pahinkar, Darshan Gopalrao. Temperature swing adsorption processes for gas separation.

Degree: PhD, Mechanical Engineering, 2016, Georgia Tech

URL: http://hdl.handle.net/1853/56348

► Natural gas has become increasingly important as a fuel source with lower environmental impact; therefore, there is a growing need for scalable natural gas purification… (more)

▼ Natural gas has become increasingly important as a fuel source with lower environmental impact; therefore, there is a growing need for scalable natural gas purification systems with small footprints. Current industrial purification systems are based on absorption, membrane separation, or adsorption techniques; however, each of these technologies requires large capital costs or suffers from scalability issues. Adsorption-based separation techniques are categorized into pressure-swing adsorption (PSA) and temperature-swing adsorption (TSA). Among adsorption-based gas purification techniques, PSA has typically been preferred over TSA due to the ease of operation and reliability. TSA processes have not commonly been used for industrial gas separation due to low thermal conductivity of the adsorbent bed, which causes difficulty in desorbing impurities and regenerating the adsorbent. However, the high heat and mass transfer coefficients possible with microchannels open the possibility of using the TSA process for gas purification. This work investigated the fluid mechanics and coupled heat and mass transfer processes within a microchannel monolith with a polymer-adsorbent matrix coating the inner walls of the microchannels during TSA-based gas separation. The concept involved separation of carbon dioxide from methane by passing the feed gas through microchannels, followed by sequential flow of desorbing hot liquid, cooling liquid, and purge gas through the same microchannels. It was found that for selected operating conditions and geometries, the process showed merit when compared to current technologies. A combination of spatially- and temporally-resolved analyses was conducted to assess these processes and select optimal configurations and process parameters. Experimental validation followed, wherein the adsorption stage of the separation process in adsorbent-coated microchannels was measured and analyzed using mass spectrometry. The combination of measurements and analyses was used to develop validated models and provide design guidance for TSA processes. Advisors/Committee Members: Garimella, Srinivas (advisor), Graham, Samuel (committee member), Kumar, Satish (committee member), Jeter, Sheldon (committee member), Koros, William (committee member).

Subjects/Keywords: Temperature swing adsorption; Microchannels; Natural gas purification; Gas separation

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APA (6^th Edition):

Pahinkar, D. G. (2016). Temperature swing adsorption processes for gas separation. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/56348

Chicago Manual of Style (16^th Edition):

Pahinkar, Darshan Gopalrao. “Temperature swing adsorption processes for gas separation.” 2016. Doctoral Dissertation, Georgia Tech. Accessed March 05, 2021. http://hdl.handle.net/1853/56348.

MLA Handbook (7^th Edition):

Pahinkar, Darshan Gopalrao. “Temperature swing adsorption processes for gas separation.” 2016. Web. 05 Mar 2021.

Vancouver:

Pahinkar DG. Temperature swing adsorption processes for gas separation. [Internet] [Doctoral dissertation]. Georgia Tech; 2016. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/1853/56348.

Council of Science Editors:

Pahinkar DG. Temperature swing adsorption processes for gas separation. [Doctoral Dissertation]. Georgia Tech; 2016. Available from: http://hdl.handle.net/1853/56348

University of Texas – Austin

25. Byrne, Matthew Davidson. Effects of particle concentration and surfactant use in convective heat transfer of CuO nanofluids in microchannel flow.

Degree: MSin Engineering, Mechanical Engineering, 2011, University of Texas – Austin

URL: http://hdl.handle.net/2152/ETD-UT-2011-05-3571

► Heat exchange systems used in everything from cars to microelectronics have rapidly advanced in recent years to offer high heat transfer rates in increasingly smaller… (more)

Subjects/Keywords: Nanofluids; Heat transfer; Convection; Microchannels; Heat exchange systems

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APA (6^th Edition):

Byrne, M. D. (2011). Effects of particle concentration and surfactant use in convective heat transfer of CuO nanofluids in microchannel flow. (Masters Thesis). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/ETD-UT-2011-05-3571

Chicago Manual of Style (16^th Edition):

Byrne, Matthew Davidson. “Effects of particle concentration and surfactant use in convective heat transfer of CuO nanofluids in microchannel flow.” 2011. Masters Thesis, University of Texas – Austin. Accessed March 05, 2021. http://hdl.handle.net/2152/ETD-UT-2011-05-3571.

MLA Handbook (7^th Edition):

Byrne, Matthew Davidson. “Effects of particle concentration and surfactant use in convective heat transfer of CuO nanofluids in microchannel flow.” 2011. Web. 05 Mar 2021.

Vancouver:

Byrne MD. Effects of particle concentration and surfactant use in convective heat transfer of CuO nanofluids in microchannel flow. [Internet] [Masters thesis]. University of Texas – Austin; 2011. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/2152/ETD-UT-2011-05-3571.

Council of Science Editors:

Byrne MD. Effects of particle concentration and surfactant use in convective heat transfer of CuO nanofluids in microchannel flow. [Masters Thesis]. University of Texas – Austin; 2011. Available from: http://hdl.handle.net/2152/ETD-UT-2011-05-3571

Louisiana State University

26. Evans, Estelle. Two-phase flow in high aspect ratio, polymer microchannels for reagent delivery applications.

Degree: MSME, Mechanical Engineering, 2006, Louisiana State University

URL: etd-11132006-224239 ; https://digitalcommons.lsu.edu/gradschool_theses/963

► Multiphase flow in microfluidics is an increasingly growing field, especially in biotechnology. For instance, a steady-state slug flow would benefit lab-on-a-chip drug delivery methods.… (more)

▼ Multiphase flow in microfluidics is an increasingly growing field, especially in biotechnology. For instance, a steady-state slug flow would benefit lab-on-a-chip drug delivery methods. This flow would not only use minute amounts of reagents, but it would also decrease the sample processing time. Thus, researching a steady-state plug flow in a microchannel is beneficial to the drug delivery field. Five PMMA, directly-milled microchannels [2: Aspect Ratio 1 (with and without pressure ports, 2): Aspect ratio 2 (with and without pressure ports), and 1: Aspect Ratio 3 (without pressure ports)] were manufactured. These channels were then cleaned, and a PMMA cover slip was thermally bound. In addition, a test setup was constructed to create steady gas and liquid flows to input into the channel. The gas flow is controlled by highly-accurate and a fast gas flow controllers, and a pressurized liquid reservoir maintains a steady liquid flow rate. A microscope equipped with a CCD camera captures images of flow within the microchips. Two techniques were used to capture flow pictures: a back illumination method with a low recording frequency, and a laser illumination method with a high recorded frequency were used to capture frames. Each channel was tested by using a set liquid flow rate of either 0.05 ml/min (low) or 0.10 ml/min (high). While the liquid flow rate was held constant, the gas flow rate was incrementally adjusted by 0.05 ml/min. Frames were taken at each increment. Bubbly, slug, and annular flow regimes were observed. OPTIMAS, image processing software, was used to extract size distributions of gas bubbles and liquid plugs and to extract bubble velocities. Bubble and plug size distributions were use to assess whether or not the flow is steady state. For the low liquid flow of 0.05 ml/min, all channels reached a steady state. However, the volumetric flow ratio ranges of steady state are different for each channel. For the high liquid flow rate of 0.10 ml/min, steady flow was not obtained in the AR1 channels. There were some minor differences in stable flow between the non-pressure port microchannels and the corresponding pressure-ported microchannel, probably due to slight differences in machining. The maximum pressure drops in AR1 and AR2 channels were 6 and 3 PSIG. The extracted velocity data included the velocity at the centroid, minimum and maximum point on the bubble. The bubbles did not deform by much (3%) because these three velocities are relatively equal. In addition, the velocities indicate that the bubble slips in the microchannel.

Subjects/Keywords: polymer microchannels; bubbles; bubbly flow; microchannels; two-phase flow; reagent delivery

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APA (6^th Edition):

Evans, E. (2006). Two-phase flow in high aspect ratio, polymer microchannels for reagent delivery applications. (Masters Thesis). Louisiana State University. Retrieved from etd-11132006-224239 ; https://digitalcommons.lsu.edu/gradschool_theses/963

Chicago Manual of Style (16^th Edition):

Evans, Estelle. “Two-phase flow in high aspect ratio, polymer microchannels for reagent delivery applications.” 2006. Masters Thesis, Louisiana State University. Accessed March 05, 2021. etd-11132006-224239 ; https://digitalcommons.lsu.edu/gradschool_theses/963.

MLA Handbook (7^th Edition):

Evans, Estelle. “Two-phase flow in high aspect ratio, polymer microchannels for reagent delivery applications.” 2006. Web. 05 Mar 2021.

Vancouver:

Evans E. Two-phase flow in high aspect ratio, polymer microchannels for reagent delivery applications. [Internet] [Masters thesis]. Louisiana State University; 2006. [cited 2021 Mar 05]. Available from: etd-11132006-224239 ; https://digitalcommons.lsu.edu/gradschool_theses/963.

Council of Science Editors:

Evans E. Two-phase flow in high aspect ratio, polymer microchannels for reagent delivery applications. [Masters Thesis]. Louisiana State University; 2006. Available from: etd-11132006-224239 ; https://digitalcommons.lsu.edu/gradschool_theses/963

Rochester Institute of Technology

27. Mehta, Jeet. Enhanced pool boiling of water with open microchannels over cylindrical tubes.

Degree: MS, Mechanical Engineering, 2013, Rochester Institute of Technology

URL: https://scholarworks.rit.edu/theses/6956

► Pool boiling is a stable and efficient method for transferring large quantities of heat. It is employed in a wide range of applications, including… (more)

▼ Pool boiling is a stable and efficient method for transferring large quantities of heat. It is employed in a wide range of applications, including steam generation in boilers, petrochemical, pharmaceutical, cryogenic and many other industrial processes. The objective of this work was to investigate the augmentation in the boiling heat transfer rates with an array of open microchannels over a cylindrical tube. In order to develop high performance surfaces, rectangular and V-groove cross-sectional geometry microchannels were fabricated and tested over tubular test sections. These microchannels were manufactured in two configurations: circumferentially around the test section and axially along the length. The effects of the microchannel geometric parameters on pool boiling performance were studied under horizontal and vertical orientations. Twenty uniquely modified microchannel surfaces were designed, fabricated and tested. The best performance was obtained with a circumferential rectangular microchannel test section in the horizontal orientation. A maximum heat transfer coefficient of 129 kW/m2*K was achieved at a heat flux of 1095 kW/m2, while maintaining a wall superheat of 8.5 K. The overall enhancement factors obtained at the maximum heat flux condition, ranged between 1.9 and 3.4 in the horizontal orientation, and 2.1 and 3.1 in the vertical orientation. The critical heat flux for almost all the designed test surfaces was increased by a factor of at least 1.6 over a plain tube. Area normalized results indicated that factors other than area enhancement are responsible for augmenting the heat transfer performance. High-speed videography of bubbles nucleating, growing and departing from the heated surface was performed. The bubble behavior over these open microchannels was analyzed to understand the fundamental mechanism during pool boiling. The bubble interactions in and over the open microchannels, and the liquid rewetting phenomenon greatly influence the heat transfer performance for these surface. Advisors/Committee Members: Kandlikar, Satish.

Subjects/Keywords: Bubble dynamics; Critical heat flux; Heat transfer enhancement; Open microchannels; Pool boiling; Tube orientation

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APA (6^th Edition):

Mehta, J. (2013). Enhanced pool boiling of water with open microchannels over cylindrical tubes. (Masters Thesis). Rochester Institute of Technology. Retrieved from https://scholarworks.rit.edu/theses/6956

Chicago Manual of Style (16^th Edition):

Mehta, Jeet. “Enhanced pool boiling of water with open microchannels over cylindrical tubes.” 2013. Masters Thesis, Rochester Institute of Technology. Accessed March 05, 2021. https://scholarworks.rit.edu/theses/6956.

MLA Handbook (7^th Edition):

Mehta, Jeet. “Enhanced pool boiling of water with open microchannels over cylindrical tubes.” 2013. Web. 05 Mar 2021.

Vancouver:

Mehta J. Enhanced pool boiling of water with open microchannels over cylindrical tubes. [Internet] [Masters thesis]. Rochester Institute of Technology; 2013. [cited 2021 Mar 05]. Available from: https://scholarworks.rit.edu/theses/6956.

Council of Science Editors:

Mehta J. Enhanced pool boiling of water with open microchannels over cylindrical tubes. [Masters Thesis]. Rochester Institute of Technology; 2013. Available from: https://scholarworks.rit.edu/theses/6956

Rochester Institute of Technology

28. Brackbill, Tim. Experimental investigation on the effects of surface roughness on microscale liquid flow.

Degree: Mechanical Engineering, 2008, Rochester Institute of Technology

URL: https://scholarworks.rit.edu/theses/7221

► Microfluidics has become of interest recently with shrinking device sizes. Roughness structures left from machining processes on the inside of tubes and channels that were… (more)

▼ Microfluidics has become of interest recently with shrinking device sizes. Roughness structures left from machining processes on the inside of tubes and channels that were once not a concern may now create relative roughness that exceeds 5%. Confusion still exists in the literature as to the extent of the effects of roughness on laminar flow. This work aims to experimentally examine the effects of different roughness structures on internal flows in high aspect ratio rectangular microchannels. A total of four test sections were fabricated to test samples with different patterned rough surfaces, and to also vary the two opposite surfaces forming the long faces of the channel. These test sections allowed the same roughness samples to be tested at varying relative roughnesses and allowed a systematic study on their effects on pressure drop. The first test section looked at sawtooth effects on laminar flow. The second looked at uniform roughness on laminar flow. The third looked at sawtooth roughness in turbulent flow, and the fourth looked at varying pitch sawtooth roughness in laminar flow. Rough surfaces were formed in one of two ways. The first involved making structured repeating sawtooth ridges with a ball end mill on a CNC machine. The second was using sandpaper in a crosshatch pattern to make a more unpatterned roughened surface. In this study, the Reynolds number was varied from 30 to 15,000 with degassed, deionized water as the working fluid. The experimental uncertainty in the experimental data is at worst 7.58% for friction factor and 2.67% for Reynolds number. Roughness structures varied from a lapped smooth surface with 0.2 μm roughness height to sawtooth ridges of height 117 μm. Hydraulic diameters from 198 μm to 2,349 μm were tested. The highest relative roughness tested was 24.8%. As a result of the first and second experiments, it was shown that using constricted parameters, sawtooth and uniform roughness performance could be predicted in the laminar regime. In the third experiment, it was shown that certain sawtooth roughness samples cause the results to converge to a single line for friction factor. In the fourth experiment, the pitch of sawtooth elements was shown to be a key parameter in showing when each parameter is applicable. It was found that roughness has an effect even at relative roughness values less than 5%. Lapped smooth samples showed no departure from macroscale theory at all channel diameters tested, which implies that no departure from continuum mechanics occurred at the length scales tested. This fit with what was expected. Early transitions to turbulence were seen however, showing decreasing transition Reynolds number with increasing relative roughness. The lowest turbulent transition occurred at a Reynolds number of 210, with a relative roughness of 24.8%. Most all of the roughness structures studied were found to have experimental results that were well predicted with the use of constricted parameters. However, samples with roughness elements placed at higher pitches were seen to… Advisors/Committee Members: Weinstein, Steven.

Subjects/Keywords: Internal flow; Microchannels; Roughness; Surface roughness

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

APA (6^th Edition):

Brackbill, T. (2008). Experimental investigation on the effects of surface roughness on microscale liquid flow. (Thesis). Rochester Institute of Technology. Retrieved from https://scholarworks.rit.edu/theses/7221

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Brackbill, Tim. “Experimental investigation on the effects of surface roughness on microscale liquid flow.” 2008. Thesis, Rochester Institute of Technology. Accessed March 05, 2021. https://scholarworks.rit.edu/theses/7221.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Brackbill, Tim. “Experimental investigation on the effects of surface roughness on microscale liquid flow.” 2008. Web. 05 Mar 2021.

Vancouver:

Brackbill T. Experimental investigation on the effects of surface roughness on microscale liquid flow. [Internet] [Thesis]. Rochester Institute of Technology; 2008. [cited 2021 Mar 05]. Available from: https://scholarworks.rit.edu/theses/7221.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Brackbill T. Experimental investigation on the effects of surface roughness on microscale liquid flow. [Thesis]. Rochester Institute of Technology; 2008. Available from: https://scholarworks.rit.edu/theses/7221

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Rochester Institute of Technology

29. Kalani, Ankit. Flow Boiling Heat Transfer Over Open Microchannels With Tapered Manifold.

Degree: PhD, Microsystems Engineering, 2016, Rochester Institute of Technology

URL: https://scholarworks.rit.edu/theses/8984

► Boiling can provide several orders of magnitude higher performance than a traditional air cooled system in electronics cooling application. It can dissipate large quantities… (more)

Subjects/Keywords: Flow boiling heat transfer; Flow visualization; High heat flux cooling; Microchannels; Pressure drop modeling

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

APA (6^th Edition):

Kalani, A. (2016). Flow Boiling Heat Transfer Over Open Microchannels With Tapered Manifold. (Doctoral Dissertation). Rochester Institute of Technology. Retrieved from https://scholarworks.rit.edu/theses/8984

Chicago Manual of Style (16^th Edition):

Kalani, Ankit. “Flow Boiling Heat Transfer Over Open Microchannels With Tapered Manifold.” 2016. Doctoral Dissertation, Rochester Institute of Technology. Accessed March 05, 2021. https://scholarworks.rit.edu/theses/8984.

MLA Handbook (7^th Edition):

Kalani, Ankit. “Flow Boiling Heat Transfer Over Open Microchannels With Tapered Manifold.” 2016. Web. 05 Mar 2021.

Vancouver:

Kalani A. Flow Boiling Heat Transfer Over Open Microchannels With Tapered Manifold. [Internet] [Doctoral dissertation]. Rochester Institute of Technology; 2016. [cited 2021 Mar 05]. Available from: https://scholarworks.rit.edu/theses/8984.

Council of Science Editors:

Kalani A. Flow Boiling Heat Transfer Over Open Microchannels With Tapered Manifold. [Doctoral Dissertation]. Rochester Institute of Technology; 2016. Available from: https://scholarworks.rit.edu/theses/8984

Texas A&M University

30. Damodharan, Shalini. Determination of Optimal Process Flowrates and Reactor Design for Autothermal Hydrogen Production in a Heat-Integrated Ceramic Microchannel Network.

Degree: MS, Chemical Engineering, 2012, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-10851

► The present work aimed at designing a thermally efficient microreactor system coupling methanol steam reforming with methanol combustion for autothermal hydrogen production. A preliminary study… (more)

▼ The present work aimed at designing a thermally efficient microreactor system coupling methanol steam reforming with methanol combustion for autothermal hydrogen production. A preliminary study was performed by analyzing three prototype reactor configurations to identify the optimal radial distribution pattern upon enhancing the reactor self-insulation. The annular heat integration pattern of Architecture C showed superior performance in providing efficient heat retention to the system with a 50 - 150 degrees C decrease in maximum external-surface temperature. Detailed work was performed using Architecture C configuration to optimize the catalyst placement in the microreactor network, and optimize reforming and combustion flows, using no third coolant line. The optimized combustion and reforming catalyst configuration prevented the hot-spot migration from the reactor midpoint and enabled stable reactor operation at all process flowrates studied. Best results were obtained at high reforming flowrates (1800 sccm) with an increase in combustion flowrate (300 sccm) with the net H2 yield of 53% and thermal efficiency of >80% from methanol with minimal insulation to the heatintegrated microchannel network. The use of the third bank of channels for recuperative heat exchange by four different reactor configurations was explored to further enhance the reactor performance; the maximum overall hydrogen yield was increased to 58% by preheating the reforming stream in the outer 16 heat retention channels. An initial 3-D COMSOL model of the 25-channeled heat-exchanger microreactor was developed to predict the reactor hotspot shape, location, optimum process flowrates and substrate thermal conductivity. This study indicated that low thermal conductivity materials (e.g. ceramics, glass) provides enhanced efficiencies than high conductivity materials (e.g. silicon, stainless steel), by maintaining substantial thermal gradients in the system through minimization of axial heat conduction. Final summary of the study included the determination of system energy density; a gravimetric energy density of 169.34 Wh/kg and a volumetric energy density of 506.02 Wh/l were achieved from brass architectures for 10 hrs operation, which is higher than the energy density of Li-Ion batteries (120 Wh/kg and 350 Wh/l). Overall, this research successfully established the optimal process flowrates and reactor design to enhance the potential of a thermally-efficient heat-exchanger microchannel network for autothermal hydrogen production in portable applications. Advisors/Committee Members: Wilhite, Benjamin (advisor), Shantz, Dan (committee member), Gentleman, Molly (committee member).

Subjects/Keywords: Microreactor; Hydrogen; Methanol; Combustion; Steam Reforming; Process Intensification; Autothermal; Portable; Ceramic microchannels; Cordierite

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

APA (6^th Edition):

Damodharan, S. (2012). Determination of Optimal Process Flowrates and Reactor Design for Autothermal Hydrogen Production in a Heat-Integrated Ceramic Microchannel Network. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-10851

Chicago Manual of Style (16^th Edition):

Damodharan, Shalini. “Determination of Optimal Process Flowrates and Reactor Design for Autothermal Hydrogen Production in a Heat-Integrated Ceramic Microchannel Network.” 2012. Masters Thesis, Texas A&M University. Accessed March 05, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-10851.

MLA Handbook (7^th Edition):

Damodharan, Shalini. “Determination of Optimal Process Flowrates and Reactor Design for Autothermal Hydrogen Production in a Heat-Integrated Ceramic Microchannel Network.” 2012. Web. 05 Mar 2021.

Vancouver:

Damodharan S. Determination of Optimal Process Flowrates and Reactor Design for Autothermal Hydrogen Production in a Heat-Integrated Ceramic Microchannel Network. [Internet] [Masters thesis]. Texas A&M University; 2012. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-10851.

Council of Science Editors:

Damodharan S. Determination of Optimal Process Flowrates and Reactor Design for Autothermal Hydrogen Production in a Heat-Integrated Ceramic Microchannel Network. [Masters Thesis]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-10851

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