【作者】 胡站伟； 李兴华； 徐胜金； 张卫国；

【Author】 Hu Zhan-wei~(1,2),Li Xinghua~3,Xu Sheng-Jin~1,Zhang Wei-Guo~2 (Fluid Dynamics Institute,School of Aerospace,Tsinghua University,Beijing 100084,China;China Aerodynamics Research & Development Center, Low-Speed Institute,Mianyang 621000,China;Department of Mathematics,Harbin University of Science and Technology,Harbin 150080,China)

【机构】 清华大学航空航天学院流体力学所； 中国空气动力研究与发展中心； 哈尔滨理工大学数学系；

【摘要】 着眼于减小PIV测试的误差和提高测试效率,使用热线和PIV设备,对直流风洞中Re=3900(以圆柱直径定义)的圆柱扰流尾迹流场进行了测量和分析。以热线测量结果作为基准,分析了PIV分析中不同问讯窗口尺寸和图像对数,对雷诺应力测量精准度的影响.同时讨论了不同湍流度下使用PIV测量雷诺应力的可行性。通过分析问讯窗口尺寸对应的截断频率与流场功率谱的关系,定性给出了问讯窗口尺寸对应的截止频率处于功率谱曲线的高频噪音区前端的选择依据。通过分析问讯窗口尺寸对应的特征时间与流场速度相关特征时间的关系,给定了PlV图像对数选择的经验公式。PIV测量结果显示,雷诺应力的准确测量对于PIV问讯窗口尺寸严重依赖,因此自适应窗口PIV是处理这类问题的方向。更多还原

【Abstract】 Aiming to reduce the random error and improve the test efficiency in in Reynolds stress measurement with PIV,a flow over a circular cylinder at Reynolds number 3900(based on the cylinder diameter) in a direct-action wind tunnel,was taken detail measurement with both PIV and HWA.With the HWA result as the standard value,PIV result with different interrogation window sizes or image pairs was compared to show the influence of these parameters,performing the limit of Reynolds stress measurement with PIV in large turbulence intensity.With the comparing of flow power spectral density and the frequency which interrogation window size corresponds to,an optimize option of interrogation window size is found referring to the root of the high noise frequency. A minimum number of image pairs is assessed with the flow characteristic correlation time and a scale time of the interrogation window size.The analysis demonstrates a high dependence of interrogation window size in the accuracy of Reynolds stress measurement with traditional PIV,indicating a potential of adaptive PIV.更多还原