High-speed flows have consistently presented significant challenges to experimental research due to their complex and unsteady characteristics.This study investigates the use of the megahertz-frequency particle image ...High-speed flows have consistently presented significant challenges to experimental research due to their complex and unsteady characteristics.This study investigates the use of the megahertz-frequency particle image velocimetry(MHz-PIV)technique to enhance time resolution under high-speed flow conditions.In our experiments,five high-speed cameras were utilized in rapid succession to capture images of the same measurement area,achieving ultra-high time resolution particle image data.Through advanced image processing techniques,we corrected optical distortions and identified common areas among the captured images.The implementation of a sliding average algorithm,along with spectral analysis of the compressible turbulent flow field based on velocity data,facilitated a comprehensive analysis.The results confirm the capability of MHz-PIV for high-frequency sampling,significantly reducing reliance on individual camera performance.This approach offers a refined measurement method with superior spatiotemporal resolution for high-speed flow experiments.展开更多
基金supported by the National Key Research and Development Program of China(Grant No.2020YFA0405700).
文摘High-speed flows have consistently presented significant challenges to experimental research due to their complex and unsteady characteristics.This study investigates the use of the megahertz-frequency particle image velocimetry(MHz-PIV)technique to enhance time resolution under high-speed flow conditions.In our experiments,five high-speed cameras were utilized in rapid succession to capture images of the same measurement area,achieving ultra-high time resolution particle image data.Through advanced image processing techniques,we corrected optical distortions and identified common areas among the captured images.The implementation of a sliding average algorithm,along with spectral analysis of the compressible turbulent flow field based on velocity data,facilitated a comprehensive analysis.The results confirm the capability of MHz-PIV for high-frequency sampling,significantly reducing reliance on individual camera performance.This approach offers a refined measurement method with superior spatiotemporal resolution for high-speed flow experiments.