The Research Of Exhaust Cooling System On Aero-engine Simulating Altitude Test Bed

Test bed which has the ability to test high-altitude simulation is a major aero-engine test equipment, the high-altitude simulation test is the key to the finalize the test of the engine. History of development research in many country’s engine has proven that aero-engine with simulated altitude test cell testing capacity is essential for the development of advanced aero-engine test equipment. In particular, modern supersonic aircraft with turbojet and turbofan engine has reached the maximum altitude of25-30km, the mach number has reached2.5-3.0.Under such a wide range of engine operating parameters, the parameters has a significant change. Therefore, there is a obvious difference between high-altitude performance and the ground performance of the engine,and also performance of the ground test can no longer be converted with similar methods to get the high-altitude performance of the engine. More importantly, with the expansion of the scope of the flight, the sea-level static condition doesn’t do impact on the engine structural strength of the worst air heat load point, but the low number of Ma in low or middle altitude do.When Germany had established the first high-altitude engine test bed in1937. the United States. Britain. France, the former Soviet Union and China have established a high-altitude bed gradually, includes different types of power plants, large air base, a hundred high-altitude test chambers, and the countless components of test equipment, which has played a great importance for the development of aero-engine. For China, the first high-altitude simulated test bed was erected in1995which had taken almost30yeas for its construction.Due to the complex of simulated high-altitude aircraft engine test bed, this paper only does some research on the exhaust cooling system. In the light of some existing domestic test beds, the main purpose is to optimize and get first-hand the theoretical data, and also for making the station technical reserves of debug applications in future.Firstly, the paper gives a brief introduction about the simulated altitude aircraft engine test bed study from abroad and the corresponding dynamic results, and then summarizes some of the traditional design methods of the aero-engine high-altitude simulation test bed. Basing on some existing experiences and the characteristics of the engine in China Aviation Power plant Institution, to provide a more practical design to maximize it’s efficiency. Secondly, after establishing a3D model, then using the flow analysis software CFX to analyze the distribution and cooling sections of the exhaust system.Finally, contrasting with the test data, it can improve each internal structure of the exhaust cooling so as to achieve maximum efficiency, and expand the range of test equipment.The study result shows that the design is feasible, effective, and also has great significance on unborn aero-engine test.