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You searched for +publisher:"Penn State University" +contributor:("Jacqueline Antonia O\'Connor, Thesis Advisor/Co-Advisor"). Showing records 1 – 3 of 3 total matches.

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Penn State University

1. Leonetti, Michael John. RQL Combustor Dilution Hole Placement and its Effect on the Turbine Inlet Flowfield.

Degree: 2016, Penn State University

Dilution jets in a gas turbine combustor are used to oxidize remaining fuel from the main flame zone in the combustor, and to homogenize the temperature field upstream of the turbine section through highly turbulent mixing. The high-momentum injection generates high levels of turbulence and very effective turbulent mixing. However, mean flow distortions and large-scale turbulence can persist into the turbine section. Traditionally, combustor exit flowfield profiles have been obtained without the presence of vanes, and turbine inlet conditions have generally been simulated by the use of artificial turbulence generators (bar grids). Little work has been done to capture the details of the impact of the combustor’s turbulent flowfield on the turbine vane in a combined configuration. In this study, a dilution hole configuration was scaled from a RQL combustor and used in conjunction with a linear vane cascade in a large-scale, low-speed wind tunnel. Mean and turbulent flowfield data were obtained at the vane leading edge with the use of high-speed particle image velocimetry to help quantify the effect of the dilution jets in the turbine section. The dilution hole pattern was shifted (clocked) for two positions such that a large dilution jet was located directly upstream of a vane, or in-between vanes. Time-averaged results show that the large dilution jets have a significant impact on the magnitude and orientation of the flow entering the turbine. Turbulence levels of 40% or greater were observed approaching the vane leading edge, with integral length scales of approximately 40% of the dilution jet diameter. Incidence angle, turbulence levels, and localized pockets of high-velocity regions were dependent on the position of the dilution jets relative to the vane. Advisors/Committee Members: Stephen P Lynch, Thesis Advisor/Co-Advisor, Jacqueline Antonia O'connor, Thesis Advisor/Co-Advisor.

Subjects/Keywords: combustor; dilution; piv; turbulence; turbine

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

APA (6th Edition):

Leonetti, M. J. (2016). RQL Combustor Dilution Hole Placement and its Effect on the Turbine Inlet Flowfield. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/28681

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

Chicago Manual of Style (16th Edition):

Leonetti, Michael John. “RQL Combustor Dilution Hole Placement and its Effect on the Turbine Inlet Flowfield.” 2016. Thesis, Penn State University. Accessed May 08, 2021. https://submit-etda.libraries.psu.edu/catalog/28681.

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

MLA Handbook (7th Edition):

Leonetti, Michael John. “RQL Combustor Dilution Hole Placement and its Effect on the Turbine Inlet Flowfield.” 2016. Web. 08 May 2021.

Vancouver:

Leonetti MJ. RQL Combustor Dilution Hole Placement and its Effect on the Turbine Inlet Flowfield. [Internet] [Thesis]. Penn State University; 2016. [cited 2021 May 08]. Available from: https://submit-etda.libraries.psu.edu/catalog/28681.

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

Council of Science Editors:

Leonetti MJ. RQL Combustor Dilution Hole Placement and its Effect on the Turbine Inlet Flowfield. [Thesis]. Penn State University; 2016. Available from: https://submit-etda.libraries.psu.edu/catalog/28681

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


Penn State University

2. Strollo, John. The Effects of Hydrogen on Steady-State and Transient Combustion Characteristics.

Degree: 2020, Penn State University

This thesis examines the effects of steady-state and transient hydrogen enrichment on thermo-acoustic instability in a model gas turbine combustor. Combustion instability, a feedback loop between flame heat release rate oscillations and combustor acoustics, is characterized in a swirl-stabilized flame operated at a range of hydrogen-natural gas fuel blends, heat rates, and mixing strategies. Measurements of combustor chamber pressure fluctuations and CH* chemiluminescence imaging are used to characterize instability at a range of operating conditions. Steady-state tests show that mixture heat rate, hydrogen content, and mixing strategy affect system stability. At a given heat rate, higher levels of hydrogen result in unstable combustion. As heat rate increases, instability occurs at generally lower concentrations of hydrogen in the fuel. While different mixing strategies yielded different stability map results, these two general trends remained. Utilization of technically premixed fuel was shown to alter the spectral density behavior of the combustor at various combustor states. This alteration of behavior was found in the form of multiple frequency peaks for various operating conditions. Steady-state flame imaging indicated general trends of increased mean and RMS CH* intensity with heat rate. For a given heat rate, all mixing strategies showed flame height reduction with increases in hydrogen content. All mixing strategies showed evidence of a nodal line (between the outer recirculation zone and upper flame region) in the RMS chemiluminescence images, where flame oscillation was at a minimum. While the fully premixed natural gas / fully premixed hydrogen and fully premixed natural gas / technically premixed hydrogen mixing strategies were generally axisymmetric, the images captured for the technically premixed natural gas / technically premixed hydrogen mixing strategy showed clear asymmetry in CH* distribution. Transient operation was tested for the fully premixed natural gas / technically premixed hydrogen mixing strategy in two directions – instability onset and decay – and two hydrogen-addition times – a short time of 1 millisecond and a longer time of 4 seconds. Results show that instability onset processes, through the transient addition of hydrogen, are highly repeatable regardless of the timescale of hydrogen addition. Certain instability decay processes are less repeatable, resulting in cases that do not fully transition from unstable to stable combustion despite similar changes in hydrogen fuel flow rate. Flame behavior before, during, and after the transient is characterized using high-speed CH* chemiluminescence imaging. Analysis of the high-speed images showed changes in flame stabilization and dynamics during the onset and decay processes. Finally, a steady-state stability map was generated for the multi-nozzle configuration of this combustor. Operating conditions for this configuration were set for the center nozzle of the combustor to match operating points for the single nozzle tests, yielding… Advisors/Committee Members: Jacqueline Antonia O'Connor, Thesis Advisor/Co-Advisor, Richard A Yetter, Committee Member, Karen Ann Thole, Program Head/Chair.

Subjects/Keywords: thermoacoustic instability; transient operation; hydrogen enrichment; thermo-acoustic instability; transient operation; hydrogen enrichment

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

APA (6th Edition):

Strollo, J. (2020). The Effects of Hydrogen on Steady-State and Transient Combustion Characteristics. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/17595jxs2469

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

Chicago Manual of Style (16th Edition):

Strollo, John. “The Effects of Hydrogen on Steady-State and Transient Combustion Characteristics.” 2020. Thesis, Penn State University. Accessed May 08, 2021. https://submit-etda.libraries.psu.edu/catalog/17595jxs2469.

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

MLA Handbook (7th Edition):

Strollo, John. “The Effects of Hydrogen on Steady-State and Transient Combustion Characteristics.” 2020. Web. 08 May 2021.

Vancouver:

Strollo J. The Effects of Hydrogen on Steady-State and Transient Combustion Characteristics. [Internet] [Thesis]. Penn State University; 2020. [cited 2021 May 08]. Available from: https://submit-etda.libraries.psu.edu/catalog/17595jxs2469.

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

Council of Science Editors:

Strollo J. The Effects of Hydrogen on Steady-State and Transient Combustion Characteristics. [Thesis]. Penn State University; 2020. Available from: https://submit-etda.libraries.psu.edu/catalog/17595jxs2469

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


Penn State University

3. Borz, Meghan Justine. GAS JET STUDIES FOR THE CHARACTERIZATION OF ADVANCED INJECTION SCHEDULES AND BOWL DESIGN IN DIESEL ENGINES.

Degree: 2016, Penn State University

In-cylinder strategies such as advanced fuel injection schedules and optimal piston bowl designs are often utilized in diesel combustion for to improve efficiency and/or reduce emissions. The large design space for injection schedules makes choosing the optimal schedule for an engine particularly challenging. Additionally, experimental in-engine studies of advanced injection schedules are time-consuming and costly. Gas jet experiments can provide a good approximation for the behavior of diesel jets and more tests can be conducted in a shorter period of time without incurring the costs of an engine research facility. The goal of this work is to gain a further understanding of some of the fundamental fluid mechanics of multiple injections, jet-jet interactions, and jets impinging on surfaces. Gas jet experiments are conducted using z-schlieren and acetone tracer planar laser-induced fluorescence (PLIF). Three studies are conducted focusing on free jets, multiple jet interactions, jet-jet interaction, and bowl geometry effects. The first study is a comparison of penetration results for helium gas jets with penetration results for vaporizing and non-vaporizing sprays, which shows that by non-dimensionalizing the results of gas jet experiments, the penetration curve follows a similar trend to the non-dimensionalized penetration curve for vaporizing and non-vaporizing liquid sprays. The second study explores the fluid mechanic interactions between multiple injections and the effects of injection duration and dwell. The schlieren results of the multiple-injection studies showed that before the end of injection (EOI) the non-dimensional jet-tip penetration was not significantly different for the first and second injection, however, the average dispersion half angle during the quasi-steady portion of injection was higher for the first injection than for the second injection. There are two multiple-injection cases where the average dispersion half angle of the second injection is higher than that of the first injection by a statistically significant amount. These differences in jet dispersion angle are indicative of differences in mixing and entrainment during the first and second injections. Future studies with acetone-PLIF will allow the concentration to be quantified and differences in the jet composition for the first and second injections in multiple-injection schemes to be compared. The last study focuses on the effects of piston bowl geometry and the angle between interacting jets. The effects of the geometry on fluid recirculation and mixing are studied using schlieren and PLIF with jets of acetone vapor and air and two different piston bowl designs. The results showed that a deeper bowl and wider angle between the jets allows for improved mixing and air utilization. Advisors/Committee Members: Jacqueline Antonia O'Connor, Thesis Advisor/Co-Advisor, Daniel Connell Haworth, Committee Member, Mary I Frecker, Committee Member.

Subjects/Keywords: gas jet; compression ignition; schlieren; jet-tip penetration; multiple injections; pilot injection; post injection; split injection; laser induced fluorescence; jet-jet interaction; piston geometry

Record DetailsSimilar RecordsGoogle PlusoneFacebookTwitterCiteULikeMendeleyreddit

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

APA (6th Edition):

Borz, M. J. (2016). GAS JET STUDIES FOR THE CHARACTERIZATION OF ADVANCED INJECTION SCHEDULES AND BOWL DESIGN IN DIESEL ENGINES. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/2j62s484w

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

Chicago Manual of Style (16th Edition):

Borz, Meghan Justine. “GAS JET STUDIES FOR THE CHARACTERIZATION OF ADVANCED INJECTION SCHEDULES AND BOWL DESIGN IN DIESEL ENGINES.” 2016. Thesis, Penn State University. Accessed May 08, 2021. https://submit-etda.libraries.psu.edu/catalog/2j62s484w.

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

MLA Handbook (7th Edition):

Borz, Meghan Justine. “GAS JET STUDIES FOR THE CHARACTERIZATION OF ADVANCED INJECTION SCHEDULES AND BOWL DESIGN IN DIESEL ENGINES.” 2016. Web. 08 May 2021.

Vancouver:

Borz MJ. GAS JET STUDIES FOR THE CHARACTERIZATION OF ADVANCED INJECTION SCHEDULES AND BOWL DESIGN IN DIESEL ENGINES. [Internet] [Thesis]. Penn State University; 2016. [cited 2021 May 08]. Available from: https://submit-etda.libraries.psu.edu/catalog/2j62s484w.

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

Council of Science Editors:

Borz MJ. GAS JET STUDIES FOR THE CHARACTERIZATION OF ADVANCED INJECTION SCHEDULES AND BOWL DESIGN IN DIESEL ENGINES. [Thesis]. Penn State University; 2016. Available from: https://submit-etda.libraries.psu.edu/catalog/2j62s484w

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

.