Session: Student Poster Competition

Submission Number: 187167

Determination of Pressure From Velocimetry Data for Incompressible and Compressible Flows 

Simultaneous pressure and velocity measurements of compressible flows are essential for understanding fundamental flow phenomena such as shockwave-boundary layer interactions, influence of surface cooling/film cooling, or supersonic jet noise. Of particular interest is development of non-intrusive, spatially resolved techniques since probes can interfere with the flow, and spatial resolution of complex flow interactions is important to identify sources of noise. Recent developments in particle image velocimetry have shown that by measuring the velocity field and its gradients, the pressure field can be inferred with adequate boundary information and assumptions about the flow (namely, either that it is incompressible, or is adiabatic if compressible). To evaluate the accuracy of obtaining pressure from velocimetry data, a first stage turbine vane with a ceramic matrix composite weave topology was tested in a low-speed linear cascade at exit Reynolds numbers ranging from 430,000 to 960,000. A transonic vane was also experimentally tested in a high-speed linear cascade at exit Mach numbers ranging from 0.7 to 1.1 and various Reynolds numbers. Particle image velocimetry was utilized to acquire the mean velocity field in the wake region downstream of each airfoil, and the mean total pressure for these adiabatic flowfields was determined using a previously described omni-directional integration procedure. For validation, probe traverses were conducted to acquire “ground-truth” data for comparison to pressure from velocimetry data. This study showed that mean total pressure can be determined from velocimetry data for both incompressible and compressible flows. Future work will investigate the use of thermographic particle image velocimetry to simultaneously acquire velocity, pressure, and temperature.

 

Presenting Author: Matthew Krull Penn State

Presenting Author Biography: Matthew Krull is a graduate student and NASA AAVP fellow at Penn State University pursuing a Ph.D. in Mechanical Engineering. He is also working on research at the Penn State ExCCL Lab studying non-intrusive flow characterization and turbine blade cooling, where he obtained his Master of Science in Mechanical Engineering. He received his Bachelor of Science in Mechanical Engineering and a minor in Physics at Penn State Behrend.

Authors:

Matthew Krull Penn State
Stephen Lynch Penn State