Study On Pneumatic Supersonic Jet Impact Test Bench

As a common phenomenon in aerospace technology, the impact of gas jet impact has been paid more and more attention, and the pneumatic supersonic jet impact test platform is used as a safety testing technology, at present, the various countries in the field is increasing input and have developed a series of related products. The goal of this topic is to research a kind of gas jet impact test platform, which can be rapidly firing by pneumatic system and can set up jet thrust that we need in a short period of time .Air flow at the outlet should achieve supersonic flow. The thrust range can be adjusted in a certain range.This paper mainly carried out the following aspects of the work:First of all, this paper introduces the characteristics of pneumatic supersonic jet impact test platform and the development status at home and abroad. According to the working characteristics and performance requirements of the test platform, the overall scheme of the test platform is determined, and then the structure of the test platform is designed. The acceleration principle and pipe flow characteristics of the inner flow in Laval nozzle are analyzed. Based on these, the calculation method of mass flow and test thrust is studied.Based on the above research, the Laval nozzle for test platform is designed required.Secondly, the jet performance of Laval nozzle is studied. Based on CFD technology and numerical simulation method, the flow field of nozzle under different inlet pressure is simulated. The simulation results are analyzed,and the inner flow of the nozzle is optimized and simulated again. The simulation results show that the optimization of the internal flow field can improve the performance of the jet.Then, the firing dynamics of firing mechanism of pneumatic supersonic jet impact test platform is studied. The dynamics analysis of moving parts and gas in the Laval nozzle are studied in the process of firing, the kinetic model of test thrust of the nozzle exit is established. Then dynamic simulation is conducted with using MATLAB. The simulation results show that the firing device can meet the test requirements of rapid firing, and can establish the required thrust of test.Finally, Simulation and analysis of the key components of the test bench is studied ,this paper carry out the static,modal and dynamics analysis of the test platform system in this environment with using the finite element analysis software ANSYS. The simulation results show that the strength of the test platform can meet the requirements of the test platform, at the same time the firing mechanism can meet the test requirements of rapid firing and it's safe and reliable during firing.