Compressor cascade for secondary flow investigation
A high speed compressor cascade wind tunnel is used for investigations of secondary flow phenomena occurring in the region between corner and side wall of axial compressors. The objective of the research is efficiency increase of turbo machinery. Realistic Mach and Reynolds number (Re <= 600000, Ma<0.7) of a axial compressor can be reached in the experimental set up. The inlet side wall boundary layer can be adjusted. The stagger and inflow angle of the examined profiles can be modified independently. For test purposes complete rows of compressor airfoils can be exchanged in short time.
Pressure measurements combined with an automated data acquisition allow recording and evaluation of parameter studies in a short period. Additional measurement technology for deeper insight into the flow include 5 hole probe for capturing of all velocity components at a time. Oil streak patterns is used as a means for surface flow visualization to determine the flow topology qualitatively. The more detailed and sophisticated method PIV or Stereo PIV is used to obtain instantaneous velocity measurements and related properties of the flow field in the compressor passage.
Parameters at Cascade Wind Tunnel
Sketch of the Cascade Wind Tunnel
Cascade with pressure probes
An overview of recent projects at the Cascade Wind Tunnel:
Active Flow Control
Passive Flow Control