Indirect measuring method for hypersonic speed wind tunnel turbulence scale

Abstract

The invention relates to wind tunnel turbulence scale measuring, in particular to an indirect measuring method for hypersonic speed wind tunnel turbulence scale. According to the indirection measuring method for hypersonic speed wind tunnel turbulence scale, a miniature airspeed head is used for measuring pressure pulsation in a hypersonic speed wind tunnel flow field, and then the turbulence scale is indirectly obtained according to relation conversion between pressure pulsation and speed pulsation. The method includes the steps of wind tunnel data collecting and data analyzing. According to wind tunnel data collection process, an adjustable device of the miniature airspeed tube is used for measuring pulsation pressure values at different positions of wind tunnel incoming flows, and other probes are used for measuring other wind tunnel data. According to the data analyzing process, the measured pressure pulsation values and other wind tunnel data are analyzed to obtain the function relation expression between pressure pulsation and speed pulsation in hypersonic speed airflows through deduction, and therefore the hypersonic speed wind tunnel turbulence scale is obtained through calculation. The function relation expression between pressure pulsation and speed pulsation is simple and clear, the hypersonic speed wind tunnel turbulence scale can be obtained only by pressure pulsation measurement and simple calculation, and the indirect measuring method is convenient and rapid to implement.

Description

technical field [0001] The invention relates to the field of wind tunnel turbulence degree measurement, in particular to an indirect measurement method for hypersonic wind tunnel turbulence degree. Background technique [0002] It is found that the degree of turbulence has an important influence on the transition of the boundary layer, and its influence on the aerodynamic measurement is as serious as the Reynolds number. At the same time, when using CFD to numerically simulate the flow field, the degree of turbulence also plays a very critical role. People often need to measure or estimate the degree of turbulence before the simulation. The accuracy of the measured or estimated value of the degree of turbulence directly affects the The accuracy of the simulation results. [0003] At present, the measurement of turbulence generally uses hot wire anemometer (HWA), laser Doppler velocimetry (LDV) and particle image velocimetry system (PIV). They all calculate the turbulence de...

AI Technical Summary

Problems solved by technology

HWA has the advantages of high dynamic response frequency and high time and space resolution, but the hot wire is easy to break. In the ultra-high sonic flow field, the high temperature and high speed environment is a severe test for it.

Both LDV and PIV are non-contact flow display technologies. They have high measurement accuracy and a wide range of velocity measurement. However, in high-speed flow fields, there are disadvantages of poor tracking of tracer particles and great impact by shock waves.

Images