关键词: 源项冷却模型;变比热;气膜冷却平板;可行性;高压涡轮

Abstract: In order to solve the problem of excessive mesh caused by partitioning the cooling chamber and multi-film cooling holes with too small size, based on the NUAA-Turbo platform, a source cooling model suitable for variable specific heat conditions is established at the outlet of the film cooling hole instead of the cooling gas flowing out of the hole, and establishing a heat transfer model inside the hole simulates convective cooling in a hole. A pneumatic study of the film cooling plate example found that when the blowing ratio is 1.0, the calculated value agrees with the experimental value. When calculating the near wall with a blow ratio of 1.5, the error between the calculated value of the flow velocity and the test value is 11.1%, but less than the error of 44.4% of the commercial software. Although the normal velocity prediction of the optimized source cooling model is not very good, but the calculation accuracy is 25% improvement based on the commercial software source cooling model. In order to prove the feasibility of this method, the experimental data of isentropic Mach number and average Nusselt number of air-cooled high-pressure turbine MT1 are compared with the calculated data. It is found that the calculated values on suction and pressure surfaces are in good agreement with the experimental data. However, there are errors between the calculated and experimental values at the local positions such as the trailing edge and leading edge of the blade without cooling film coverage. The research shows that the optimized source cooling model can accurately simulate the macroscopic characteristics of the cooling jet. This method has certain application potential for the design of the gas-cooled turbine in engineering.

Key words: Source cooling model;Variable specific heat;Film cooling plate;Feasibility;High-pressure turbine