粒子成像测速法中询问域大小的选择与粒子位移量的关系

The relation between the choice of interrogation region size and the particles displacement in particle imagei velocimetry

通过分析询问域大小对底片乳剂颗粒产生的散斑噪声及其散斑噪声对干涉条纹识别的影响,推导出了询问域大小的选择与被测粒子位移量之间的关系,并详细讨论和分析了询问域的大小对所能探测的粒子位移量最大值的限止,以及合理选择询问域大小的依据.

In particle Image velocimetry, a thin laser beam is usually used to interrogate the double-exposure photographic image point by point in order to find out displacement of the particles. In this paper, the relation between the choice of interrogation region size and the displacement of the measured particles is daduced by analyzing the effect of Size of the region upon the speckle distribution and the influence of the speckle noise upon the disc-rimination of the Young's fringes. The problem that the size of the interrogation region places a restriction on the maximum displacement to be able to measure and the criteria for reasonablly choosing the interrogation region are discussed and analyzed.