Rotating Effects on Aero-Thermal Performance of a Turbine Cascade with and Without Tip Cooling

In order to clarify the effects of blade or casing rotation and tip cooling on the aero-thermal performance of turbine rotors, numerical simulations are conducted for a rotor blade of LISA one-half-stage turbine. Cooling holes are generated on the blade tip, and various coolant mass flow rates are involved. Numerical results show that under different rotating conditions, the energy loss of the cascade is the lowest when the mass flow ratio of coolant to mainstream fluid equals 0.3%, while the tip leakage mass flow rate is the smallest and the tip heat transfer quality is the highest when the mass flow ratio equals 1.0%. Blade rotation, casing rotation and casing linear moving can decrease the tip leakage loss and leakage mass flow rate. The energy loss over the upper half span area downstream of the cascade outlet is reduced by a maximum value of 26.10% under the blade rotation. With the change in the mass flow ratio, rotating effects on the tip leakage loss are not varied, but those on the total loss and tip heat transfer quality are altered. When the mass flow ratio is lower than 0.3%, the rotating blade case has lower total loss than the stationary case but higher than casing moving case. This case also has the most favorable heat transfer quality. When the mass flow ratio is higher than 0.7%, the total loss is the largest for the blade rotation case, and the heat transfer quality is the best under the casing moving condition. © 2020, Editorial Department of Journal of Propulsion Technology. All right reserved.