尾缘S₃面积比梯度对涡轮后机匣的影响

For the intergraded design of support plate and outlet guide vane, where it's difficult to apply the three-dimensional blade design, the secondary flow in the outlet guide vane can be controlled by changing S₃ area ratio gradient at the trailing edge. The numerical results of inner flow field and aerodynamics performance of three designs were compared in a 1.5 stage turbine. The results showed that when the gradient reduced from 0.01 to -0.05, the overall total pressure recovery coefficient of the outlet guide vane increased from 0.979 to 0.991, and the S parameter on 5% span reduced from 0.011 to 0.005. The back-flow zone on the hub endwall and the suction side of the blade disappeared, and the corner separation was effectively controlled. When gradient reduced from -0.05 to -0.10, the flow velocity in the corner zone increased, and at the 5% span, corner blockage lessened, axial velocity density ratio (AVDR) increased, total pressure recovery coefficient increased, yet the S parameter didn't change.