【摘要】 介绍一种粒子图象测速技术中Young氏条纹图象的计算机自动处理方法。通过一维平均-相关法由二维Young氏条纹强度分布构造的函数W(α)确定条纹方向;用正态分布函数构成的模拟函数修正衍射光晕影响;采用一维Fourier变换确定条纹间隔。这种Young氏条纹处理方法省时且具有较高的测量精度(条纹方向和间隔测量误差分別小于0.5°和1％)。更多还原

【Abstract】 A new method for the automatic processing of Young’s fringes obtained from PIV photograph is presented. The fringe orientation is determined by searching for the maximum of the function W(α) constructed from the 2-D Young’s fringe intensity distribution. The influence of the diffraction halo is removed by a simulated function constructed with normal function; the fringe spacing is derived from calculating 1-D Fourier transformation of 1-D fringe intensity distribution. Using this processing method, only a small amount of computation is required and a high measuring accuracy can be obtained (The measuring errors of fringe orientation and spacing are less than 0.5 ° and 1% respectively).更多还原