Effects of Loading Distribution on Turbine Tip Leakage Losses

Different loading forms are obtained by changing the stagger angle and thickness distribution of profile at 90% span, and the influence of loading form on tip leakage flow and loss is compared by numerical simulation method. The results show that the tip loading forms affect the flow of the leakage flow and the distribution of the normal/streamwise velocity difference along the axial direction, which affects the leakage flow loss. As the tip load moves toward the leading edge, the total leakage of the tip increases, the leakage and momentum difference are relatively uniform distribution along the axial direction, the local peak decreases, and the proportion near the middle increases. Under the joint action of the leakage and the momentum difference, position of the leakage vortex rolling moves upstream, but the mixing strength with the main stream is weakened, and the loss is reduced. The mid-load and front-load forms can effectively reduce the momentum difference between the leakage flow and the mainstream flow, reduce the leakage loss, and improve the turbine performance.