Skip to Main Content
 

Global Search Box

 
 
 

ETD Abstract Container

Abstract Header

Impact of Free-Stream Turbulence Intensity on the Endwall Region of Low Pressure Turbine Blades

Donovan, Molly Hope
http://rave.ohiolink.edu/etdc/view?acc_num=dayton1681823544653736

Abstract Details

2023, Doctor of Philosophy (Ph.D.), University of Dayton, Aerospace Engineering.
Turbomachinery components, such as the low pressure turbine, are highly complex rotating machines, therefore, conducting fundamental fluid mechanics studies in them is exceedingly difficult. For this reason, testing is generally completed in facilities such as linear cascades, like the one present in the Low Speed Wind Tunnel Facility at AFRL, which typically utilize a low freestream turbulence intensity, when in reality, the freestream turbulence intensity in a full, rotating low pressure turbine is likely much higher. Slightly elevating the freestream turbulence intensity (e.g., 3%) typically improves the Reynolds-lapse characteristics of a blade profile by affecting the transition process, reducing the detrimental effects of laminar boundary layer separation, and shifting the knee in the loss curve. Front loaded blades are more resistant to separation, however, they can experience high losses in the endwall region due to the complex vortical structures present. Therefore, a better understanding whether high levels of freestream turbulence intensity will increase the overall losses generated in the passage is important. An intial study with a jet based active grid was completed on the L2F blade. Based of the insight gained from that study, a new mechanical agitator based active grid was implemented into a linear cascade of L3FHW-LS blades in order to more effectively study how elevated FSTI impacts the endwall flow behavior and loss production. Coefficient of pressure measurements, three planes of SPIV, two additional planes of flow visualization, and three planes of total pressure loss measurements were collected. Impacts of incoming turbulence on the endwall losses as well as the endwall flow structures were assessed.
Markus Rumpfkeil (Advisor)
Christopher Marks (Committee Member)
Sidaard Gunasekaran (Committee Member)
John Clark (Committee Member)
210 p.
Aerospace Engineering
endwall flows; high turbulence intensity; endwall losses; secondary flows; turbomachinery; fluid mechanics; low-pressure turbine; endwall vortex; wall-bounded flows; LPT; turbine engine

Recommended Citations

Citations

  • Donovan, M. H. (2023). Impact of Free-Stream Turbulence Intensity on the Endwall Region of Low Pressure Turbine Blades [Doctoral dissertation, University of Dayton]. OhioLINK Electronic Theses and Dissertations Center. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1681823544653736

    APA Style (7th edition)

  • Donovan, Molly. Impact of Free-Stream Turbulence Intensity on the Endwall Region of Low Pressure Turbine Blades. 2023. University of Dayton, Doctoral dissertation. OhioLINK Electronic Theses and Dissertations Center, http://rave.ohiolink.edu/etdc/view?acc_num=dayton1681823544653736.

    MLA Style (8th edition)

  • Donovan, Molly. "Impact of Free-Stream Turbulence Intensity on the Endwall Region of Low Pressure Turbine Blades." Doctoral dissertation, University of Dayton, 2023. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1681823544653736

    Chicago Manual of Style (17th edition)

dayton1681823544653736
86
© 2023, all rights reserved.
This open access ETD is published by University of Dayton and OhioLINK.