Supersonic wind tunnel experiment is one of the important measurements for developing advanced gas turbines,and supersonic multi-hole probes are sophisticated tools to measure pneumatic parameters in such experiments....Supersonic wind tunnel experiment is one of the important measurements for developing advanced gas turbines,and supersonic multi-hole probes are sophisticated tools to measure pneumatic parameters in such experiments.However,shock waves form around the probe head in supersonic flow,which affect the accuracy of results.In this study,a supersonic five-hole probe is selected as the research object.Firstly,a compound five-hole pressure-temperature probe was designed and produced with 3D-printing technology.Then,the shock wave spectrum was numerically calculated by three methods,which were the Mach number,density gradient,and shock function;in contrast to the other two methods,the shock function could accurately identify the types and ranges of shock and expansion waves.The results show that a strong shock wave is formed at the front section of the probe head,and the shock wave generated around the pressure measuring tube affects the total pressure and Mach number of the flow field,which causes the increase of entropy.The intensity of the shock wave at the head of the pressure measuring tube is the largest,causing a decrease in the total pressure around the flow field.Afterwards,to reduce the calculation errors caused by neglecting the compressibility of gases and the entropy increase,a gas compression factor δ_(s) was introduced.It is proved that the error of the calculated pneumatic parameters is less than 5% and 10% in subsonic and supersonic condition,respectively,with the gas compression factor considered.The research results of this paper provide theoretical reference for the design and use of pneumatic probes during subsonic to supersonic flow.展开更多
基金co-supported by the National Natural Science Foundation of China(No.52236005)the Science Center for GasTurbineProject(No.P2022-B-II-007-001)the National Key Laboratory Funds(No.D5150230002).
文摘Supersonic wind tunnel experiment is one of the important measurements for developing advanced gas turbines,and supersonic multi-hole probes are sophisticated tools to measure pneumatic parameters in such experiments.However,shock waves form around the probe head in supersonic flow,which affect the accuracy of results.In this study,a supersonic five-hole probe is selected as the research object.Firstly,a compound five-hole pressure-temperature probe was designed and produced with 3D-printing technology.Then,the shock wave spectrum was numerically calculated by three methods,which were the Mach number,density gradient,and shock function;in contrast to the other two methods,the shock function could accurately identify the types and ranges of shock and expansion waves.The results show that a strong shock wave is formed at the front section of the probe head,and the shock wave generated around the pressure measuring tube affects the total pressure and Mach number of the flow field,which causes the increase of entropy.The intensity of the shock wave at the head of the pressure measuring tube is the largest,causing a decrease in the total pressure around the flow field.Afterwards,to reduce the calculation errors caused by neglecting the compressibility of gases and the entropy increase,a gas compression factor δ_(s) was introduced.It is proved that the error of the calculated pneumatic parameters is less than 5% and 10% in subsonic and supersonic condition,respectively,with the gas compression factor considered.The research results of this paper provide theoretical reference for the design and use of pneumatic probes during subsonic to supersonic flow.
