The endwall and corner region is one of the high-loss regions in compressors . The three-dimensional separation in this region, also referred to corner stall and corner separation, is an inherent flow feature in compressors. Corner stall is an important key to compressor efficiency and stability . A number of studies have been done to research the impacts, topology, influencing factors and criterions of corner stall [3–9]. Though some of the deleterious consequences of corner stall can be identified, an effective control of these effects has been very difficult to achieve. This is because neither the nature and characteristics of these separations are still not clearly understood, nor the mechanisms and factors that influence their growth and size fully quantified . Corner stall is caused mainly by the strong streamwise pressure gradient, the presence of secondary flow and the merging of the wall and the blade boundary layers, but it is beyond the scope of the boundary layer theory and secondary flow theory. Computational fluid dynamics (CFD) is a powerful tool to research corner stall, but only overall pattern of corner stall can be captured while flow details are not well computed . Right now large eddy simulation (LES) is one of the more promising modes of numerical simulation of turbulence [11, 12], but it still needs to be calibrated when using in turbomachinery.
To gain a better knowledge of the mechanisms and to calibrate CFD tools including both RANS and LES, a detailed and accurate experiment of three-dimensional flow field through a compressor cascade has been set up at LMFA. The investigation is carried out on a low-speed cascade facility consisting of 13 NACA65-009 blades.
The extensive and comprehensive data base mainly includes the following measurements : (1) Oil visualization on the blade and endwall ; (2) Inlet flow investigations with hot-wire, in freestream flow and boundary layer ; (3) Inlet flow investigations with five-hoe probe ; (4) Steady pressure on the blade at various spanwise location and on the endwall ; (5) Velocity in the passage with PIV ; (6) Exit measurement with hot-wire and five-hole probe.
These experimental and numerical works are carried out with the aim of enhancing the CFD works and the understanding of the physics of corner stalls. That will lead to solutions for the control of this important 3D separation.