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I t is a long period from the engine design to prototype. Development of an new engine has to experience the cycle process, that is design followed test till success. During the course, large number of tests have to be conducted to validate the design, engine performance, stability, reliability, operability, etc. The engine ground test facilitys are in charge of all the important ground test tasks . Thereinto, the altitude simulation test facility(ASTF) is the key equipment for its inherent predominance and powerful test ability. As one of the key parameter to demonstrate the engine performance, air massflow parameter always attract the attention of the measurement work. Unfortunely, this parameter is a indirect measured parameter which is involved with inlet total pressure, static pressure,total temperature etc, so it is effected by many factors. Especially in altitude simulation test, the engine vary in different power setting as well as the inlet flow field , it is difficult to measure air massflow accurately.The objective of this thesis is to improve the measurement method of air massflow, to promote the accuracy of air massflow. Firstly, the research begin with the methodology research, and then, the direct parameters. Through the research on these aspects such as probe structure, the section arrangement, the instrument, arithmetic, some methods ,have been find to solve the problem exist in measurement. Some advance software such as CFD is used to assist the research. At last, the improved way is supported by test results, that is, compaire with the results before the evolution of the research work, the accuracy of air massflow has been promoted in great extent.
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