关键词: 高压涡轮, 转子振动, 涡轮叶片, 气动特性, 换热特性

Abstract: In order to explore the influence of high-pressure turbine rotor vibration caused by dynamic load on the aerodynamic and heat transfer characteristics of grooved tip, the time-averaged and transient aerodynamic and thermal performance of non-air-cooled and air-cooled grooved tip under the influence of vibration were compared and analyzed by numerical simulation method. The results show that the influence of vibration on the time-averaged characteristics is limited : the average total pressure loss coefficient under the condition of no air-cooled blade tip vibration is 0.2 % lower than that without vibration ( from 0.0946 to 0.0944 ), and the fluctuation of the surface average heat transfer coefficient is less than 0.2 %. The air-cooled blade tip decreases by 3.8 % and 0.8 %, respectively. The transient analysis shows that the instantaneous leakage flow rate, the surface average total pressure loss coefficient and the heat transfer coefficient of the air-cooled tip are positively correlated with the amplitude. The heat transfer coefficients of the 10-70 % Cx region on the bottom surface of the groove and the 10-60 % Cx region on the top surface of the shoulder wall are sensitive to the amplitude change. Under the combined action of cooling air mixing and vibration, the strength of the vortex system increases, the fluctuation of the aerodynamic loss increases, and the non-uniformity of the heat transfer at the bottom of the groove increases. Among them, the heat transfer coefficient of the top surface of the trailing edge shoulder wall is significantly affected by vibration and the cold air is difficult to cover, which should be paid attention to in the design.

Key words: High pressure turbine, rotor vibration, turbine blade, aerodynamic characteristics, heat transfer characteristics