Meet Our Students

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Mary K. Jennerjohn

email: mjennerj@slu.edu

Advisor/Mentor: Mark McQuilling
Sponsor/Grant: Honeywell Aerospace
Program Start: Summer 2013

 



Biography

Mary Jennerjohn graduated with her Bachelor of Science in Aerospace Engineering in 2013 from Parks College of Saint Louis University. Through her undergraduate career, she was involved in research topics such as SPLITT Fractionation techniques for separation of micro-particles and whole blood components, jet impingement cooling for applications in turbomachinery, and elastic turbulence thermal transport. Jennerjohn is currently pursuing her Ph.D. in Aerospace Engineering with a concentration in thermal-fluid sciences. Her dissertation scope involves high pressure turbine transonic aerodynamics and secondary flow losses.

Research

Jennerjohn’s research interests include understanding the development and dissipation of aerodynamic losses in a high pressure turbine of a gas turbine engine. Her experimental work will be performed in the Parks College Polysonic Wind Tunnel (to be constructed in Spring 2015), while the computational work will be executed using SC/Tetra (Software Cradle Co., Ltd.). The three-dimensional nature of endwall flows in high pressure turbines are modeled using a linear turbine cascade. A linear cascade is a simplified version of the real 3D model, where turbine blades without twist and taper are aligned linearly and bounded on either side by a flat plate. In the current study, Jennerjohn will be utilizing this simplified geometry to analyze secondary loss mechanisms. Secondary losses are total pressure losses which develop within the turbine blade row, due to the pressure gradients imposed on the flow by the blade and its respective passage. These losses are due to the development of secondary flows in the form of the horseshoe vortex, passage vortex, counter vortex, and sometimes the corner vortex. Downstream of the blade row, these losses mix out into the mainstream fluid flow causing a reduction in the total pressure and momentum of the flow. Ultimately, the secondary losses create a problem to the gas turbine engine as it inhibits the production of energy to power the compressor leading to a reduction in engine efficiencies.