气冷涡轮导叶流热耦合计算及机理

According to the multi-field coupling characteristics of air-cooled turbine blades, numerical simulation of high-pressure turbine guide vanes with different air-cooling structures is carried out by the flow-heat coupling method. In internal cooling turbine blade example, by comparing the experimental data to select a higher-accuracy Conjugate Heat Transfer (CHT) calculation scheme, the multi-field characteristics and coupling mechanism of the internal cooling guide vane are analyzed. On this basis, the turbine guide vanes with film cooling holes and internal cooling channels are the research object, the interaction between cooling jet and main stream are focused on, and the fluid thermal coupling relationship in near wall boundary layer and related questions such as the factors affecting the air cooling efficiency are discussed. The results show that the use of flow-heat coupling calculation method and a suitable turbulent transition model is conducive to improving the simulation accuracy. Flow field and temperature field of the air-cooled guide vane are closely coupled, and the flow heat-transfer characteristics affect each other. In case of low speed rate, increased cool air flow can improve the cooling efficiency of the film, and if the flow of cold air is increased to a certain value, the increase in the cold flow will cause a poor upstream cooling effect behind the air-cooled hole and a better downstream cooling effect. High-speed cooling interacts with main stream, which will produce complex flow structures such as kidney-shaped vortices and horseshoe vortices that have certain influences on temperature distribution.