Effect of Stagger Angle on the Three-Dimensional Separation Around a NACA65 Blade in a Decelerating Flow

In order to examine the fundamental characteristics of a corner separation in a decelerating cascade flow, an experimental apparatus was made and the three-dimensional separation around a NACA65 blade in a decelerating channel flow was investigated experimentally. Effect of stagger angle of 14 deg. and 10 deg. on the channel flow was focused on. The experimental investigation by the five-hole probe showed that the accumulations of the low energy fluid was seen around the corner part and the overturning flow due to the secondary flow existed for 14 deg. of stagger angle, whereas the accumulations of the low energy fluid were seen at around midspan for 10 deg. of stagger angle. PIV measurement showed that various focus-type separations were seen in the flow for 10 deg. of stagger angle and threedimensional vortex structure was considered by using a vortex filament.