Study on the influence of typical aerothermal parameters on the thermal response characteristics of turbine blades in transient state

High-pressure turbine solid/internal cooling blades are selected as the research objects to systematically explore the laws governing blade thermal response characteristics under transient states with respect to cooling air, temperature rise rate, and temperature ratio. Specifically, the cooling air ratio are 0 %, 5.6 %, and 8.9 %; the temperature rise rates are 50K/60s, 50K/30s, and 50K/10s; and the temperature ratios are 1.25, 1.5, 2.0, 2.5, and 3.0. Increasing cooling air accelerates the heat transfer from mainstream to wall by strengthening convective heat transfer of inner cooling channel, which significantly inhibits the excessive temperature response of the blade surface, but is affected by mainstream temperature rise rate. At large temperature rise rate, cooling air cannot effectively take away the heat and has little effect on the thermal response. At small temperature rise rate, cooling air ratio increases from 0 % to 8.9 %, and temperature thermal response rate decreases by 10.6 %. Rising the temperature ratio, blade thermal response rate is faster, and blade heat load is higher. Reasonable internal cooling structure could effectively avoid the phenomenon. When the temperature ratio rises from 1.5 to 2.0, the overall temperature response rate of the uncooled blade increases by 24.86 %, but the internal cooling blade with a cooling air ratio of 8.9 % only increases by 13.82 %. It is evident that real-time matching design for cooling air ratio and temperature rise rate, taking into account the engine actual operating condition variations, is particularly essential.