非正交LDV测量三维速度的一些研究

Research on three-dimensional velocity measurement using nonorthogonal LDV

激光多普勒技术 (LDV)已经得到了广泛的应用 ,成为非接触测量速度场的重要工具。差动式LDV成为激光多普勒测量技术的标准以来 ,由于各种限制条件 ,一般不能直接利用正交LDV测量三维速度。而必须使用非正交LDV系统先测量得到非正交的三维速度 ,然后通过变换方程求得正交三维速度。通过理论分析 ,非正交LDV技术测量三维速度得到的一些结论对实际测量具有指导作用。

LDV provides a non-intrusive useful tool to measure the local flow velocity within a relatively small measurement volume. Since it was developed in 1969,the dual-scatter or fringe type laser velocimeter have become the universally accepted standard. But it can not easily expanded to a three-component system. The nonorthogonal velocity is measured by LDV,from which the orthogonal three-dimensional components are computed through transformation equation. In this paper,the presented measurement techniques of nonorthogonal velocity with LDV gives useful help for application of LDV.