Research Of Similarity And Dimensional Methods In Turbine Vane's Overall Aerodynamic And Cooling Performance Experiments

One of the most important methods to optimize the turbine blade is the experimental method. However, the real blade often works in a high level temperature and pressure, which is very hard to achieve in the laboratory conditions. Thus, it is very important to find a proper way to simulate the aerodynamic and heat transfer environment in low level temperature and pressure.Based on the similarity theory, it is possible to obtain scaled operating conditions using different scaling methods. Numerical simulation verified by experiment using those scaled operating conditions have been carried out to assess the performance of different scaling methods by comparing flow field structure, normalized parameters on the blade surface and performance parameters. In the blade cooling experiment, it is found that for the mainstream flow, matching both Re and Ma in real engine and lab test conditions are crucial to ensure the best possible results. However, for the coolant flow it is more important to match Re and the ratio of coolant-to-gas temperature. The optimized scaling method established in this paper can reduce the relative error from 1.98% to 1.05% for film cooling configuration, and from 4.8% to 2.75% for internal cooling configuration. In the turbine cascade aerodynamic experiment, it is shown that coolant-to-gas temperature ratio have a little influence on the normalized pressure distribution on the blade surface and energy loss coefficient.So for the turbine cascade's aerodynamic experiment, coolant-to-gas temperature ratio is a less important parameter. Howerver, it is found that the scaling inlet temperature have a significant influence on energy loss coefficient. When the scaling inlet temperature changs within 60%, a small error can be introduced in the experiment. Otherwise, a large error can be introduced in the experiment.