A Certain Type Of Low-pressure Turbine To Move Leaves Cold Efficiency Pilot Study

Aero-engine turbine blades are subject to big force and high temperature. The cooling and heat transfer technology which is directly related to efficiency,reliability and life of engine is the key point of its design. The traditional cooling test of turbine blades has been performed by the following method in our establishment. The sector cascade which is made up of five to six piece blades (middle one is the test blade with thermocouple, others are subsidiary blades) is placed on the test bed which is composed of front adapter,front measuring segment,test segment and rear measuring segment with water cooling. It should be tested under the condition of similar gecometry, similar flow and similar heat. However, this test method is not widely used due to the expansive cost and the long time needed to design and manufacture the cascade. And it is not suitable for the experimental research regarding to cooling efficiency with more kinds of turbine blades. Accordingly, the universal test cell with double deck and water cooling have been designed and manufactured to improve the situation. Different no-cooling test-subassembly for experimental study of cooling efficiency can be tested in the new facility. But there is no experience about the design and experimental study on cooling efficiency of real blades after the test cell was built.Based on the above, an experimental module of rotor blades of a low-pressure turbine was designed and manufactured for cooling test in order to fulfill the associative requests of APTD's plan. The parallel experimental study using short time and low cost on turbine blades with two kinds of cooling structure was carried out to get the relationship between the parameters effecting blade cooling and the temperature distribution on blade surface, so the better cooling structure could be distinguished. The test data could provide a reference for blade design and calculation. Meanwhile it can be used to validate the reliability and generality of the test cell and test modules.The test results show that the test data of the turbine blades employing row of cylinder and row of flat are consistent with the design, but the convection cooling effect of the latter one is better. The structure with row of flat has less cooling effect on some local suction surface. The reliability of the test cell and the correctness of the test method and data reduction method are validated by this way. The refractory steel 1Cr25Ni20Si2 used to replace high temperature alloy can meet the test requirement. This method can save a lot of money and time for the forthcoming programs which are similar with the study.