Experimental Investigation of Vortex Structure in Corner Region of a Linear Compressor Cascade

A detailed experimental investigation was carried out to examine the vortex structure in the corner region (between the end wall and the suction surface of blades) of a linear compressor cascade. A corner vortex was identified in the corner flow in the experiment. The corner vortex sheds from the pressure-driven boundary layer on the end wall in a process of three-dimensional separation. It dominates the corner flow by the strong interaction with the main flow and the boundary layer on the suction surface of blade. The difference between the corner vortex and the well-known passage vortex is discussed. A topology of the vortex structure is proposed. Furthermore, the dynamic effects of the vortex structure has been investigated, which leads to a explanation for the mechanism of corner stall in compressor cascades.