激光横向剪切干涉应用于温度场的测量

Measurement of Temperature Field Based on Laser Lateral Shearing Interferometry

摘要:

根据大空间自然对流水平圆管上部上升的羽状烟柱区不符合边界层假设而导致各种解之间差异的问题，提出了利用横向大剪切量干涉实验装置来实现温度场的光学测量，得到了自然对流水平圆管在不同壁温时的实时条纹。利用彩色条纹图像中RGB原始数据中的R分量的峰、谷极值点的坐标来识别明、暗条纹并得到了全场的级数分布，以此反演出全场温度分布。实验结果表明：当圆管直径d为156 mm、剪切量s为242mm时，实验得到的干涉条纹类似于利用全息干涉或马赫－曾得干涉原理得到的无限宽简单条纹；干涉条纹分辨率达到7564 pix/mm；利用横向大剪切量干涉法能够准确快速地反演全场温度分布，为工程热物理分析提供相关数据。

Abstract:

As the rising plume area at upper part of natural convection horizontal circular cylinder in infinite space does not meet boundary layer hypothesis which leads to differences between various solutions, lateral shearing interferometer (LSI) with large shearing quantity is designed to realize the optical measurement of temperature field. The real time interferometric fringes of natural convection around horizontal circular cylinder with different wall temperatures were obtained using LSI with large shearing quantity. The peak and valley extreme points coordinates of R value component in RGB raw data of color fringe images were employed to identify right and dark fringes and all field series distribution was obtained. And all field temperature inversion in accordance with all field series distribution was completed. Experimental results indicate that the obtained interferometric fringes are similar to the infinitely wide and simple fringes using holographic or Mach Zehnder interferometry as diameter d and shearing quantity s are 15.6mm and 24.2mm respectively. The interferometric fringes resolution is 75.64pix/mm. The inversion of all field temperature distribution using LSI with large shearing quantity can be accurately and quickly completed, the related data of engineering thermal physics analysis can be provided.