Flow-field Parameter Estimation And Tunnel Commission For A Piston-driven Expansion Tube

Hypersonic vehicle,scramjet,reentry and other projects are the focus of scientific research at China and abroad.The reliable hypersonic ground experiment equipment plays an important role in these research.At present,the hypersonic ground test equipment in China is still insufficient.In this thesis,the QH-Etube expansion tube wind tunnel of Tsinghua University is preliminarily commissioned and the operating parameters are estimated.The main contents include briefly introducing the research progress of the expansion tube wind tunnel at China and abroad,sorting out the theoretical estimation formula of the parameters of expansion tube wind tunnel,and comparing with the working condition parameters in the literature;designing and processing the flow field calibration and total pressure measurement bracket;briefly analyzing the single piston driver;adjusting and testing the synchronous control system,building the flow field schlieren measurement system,and photographing the flow field image.The theoretical calculation results are similar with those in the literature,which proves that the theoretical calculation method is correct.Through the preliminary commissioning,the expansion tube wind tunnel can be operated normally and be used in scientific experimentsThe expansion tube wind tunnel is in the initial stage of commissioning.The theoretical calculation in this thesis is based on the formula of complete gas effect and ideal shock tube,without considering the boundary layer effect.In this thesis,the diaphragm and experimental results have not been analyzed,and the next step is suggested.The theoretical estimation,experimental equipment subsystem commissioning and sensor support design in this paper lay the foundation for further commissioning of the expansion tube wind tunnel.