应用二维哈特曼(Hartmann)波前测量系统,对光束在二维低速热射流传输中的气动光学效应进行了测量。应用模式法,通过孔径斜率进行了波前重构,结果表明热射流使波前产生较强的随机畸变。同时通过对子孔径波前斜率的时间变化测量结果进行了相关函数计算,计算显示出互相关函数随空间相对位置表现出一定规律的变化,由此分析了热射流场中涡结构的运流速度、涡结构尺度等湍流中重要的特性。这些初步测量和分析结果表明通过哈特曼波前测量法既可研究光束在湍流场中引起的波前变化规律,同时还可以应用于湍流场流场参数的间接分析。

A two-dimensional Hartmann wavefront sensor is used to measure the aero-optical effects when the optical beam passes through a low velocity heat turbulent jet. The wavefronts are reconstructed by the results of the measured wavefront gradient, and the wavefront aberration is obviously shown. The correlation function is obtained from angular beam-jitter measurements, and the convection velocity and turbulence scale size of the flowing turbulence jet are calculated. These results show that the Hartmann wavefront sensor is not only used to measure the aero-optical effects in turbulent medium, but also utilized to perform non-intrusive studies of fluid flows.