Session: 40-03 Compressor Secondary Flows and Interactions

Paper Number: 129181

129181 - Wake-Separation Bubble Interaction Over an Experimentally Simulated Axial Compressor Blade Under Low Reynolds Number Flow 

For most part, the flow over an axial compressor blade is subjected to adverse pressure gradients. Under low Reynolds number conditions, the flow could separate off the blade surface especially on the suction side, where it first accelerates to a peak velocity and then decelerates to a higher-pressure condition at the blade exit. The ‘separation bubble’ thus formed could, in many cases, trigger flow transition from laminar to turbulent conditions on reattachment further downstream of the point of separation. Since blade profile losses depend on the transition location, the modification of the separation bubble due to any upstream generated disturbances is of great interest. In this paper the interaction between incoming wakes, that are generated periodically, and the separation bubble that exists on the blade surface is investigated. Results are presented from wind tunnel experiments conducted over a flat plate that is imposed with a surface pressure profile similar to that over a highly loaded compressor blade. The periodic wakes are introduced using an upstream bar passing mechanism that produces respresentative unsteady parameters. The spatial and temporal development of the flow along the mid-span region is described with the help of particle image velocimetry-based flow mapping at a relatively low Reynolds number of 210,000.

Presenting Author: Thomas Irps University of Sussex

Presenting Author Biography: Thomas Irps is currently undertaking doctoral research studies at the University of Sussex in the area of Unsteady Separated Boundary Layer Transition over Axial Compressor Blades.

Authors:

Thomas Irps University of Sussex
Vasudevan Kanjirakkad University of Sussex