流动多参数场的单帧图像法测量方法研究

在采用单帧单曝光图像法(SFSE )研究射流卷吸流场测量应用的基础上,提出了单帧多曝光图像法(SFME)。该方法不仅可以测得流场的速度场,还可以得到加速度场、力场以及湍流强度、湍流应力等多个场参数。应用 SFSE 和 SFME 方法,对圆管淹没水射流的卷吸涡结构进行高分辨率图像可视化初步测量实验研究,测量空间分辨率达到1.125μm,发现了一些未见文献报道的涡结构,清晰地显示了射流卷吸涡的发展演变过程。实验结果表明 SFSE 和 SFME 方法用于观测微米级的流场湍流流动和涡结构,可以较其他方法得到更丰富的流场参数信息。与其他流场测量方法比较,该方法测量装置简单,空间分辨率高,对实验条件要求低,能够更加直观地显示流场多参数信息并用于微观流场的测量。

Research on the single frame imaging method for measuring multi-parameter fields in flow field

This paper investigateed the application of the Single Frame and Single Exposure Imaging (SFSE)method in the jet flow field and proposed an advanced method———the Single Frame and Multiple Exposure Imaging (SFME)method,which can measure not only the velocity field but also the acceleration field,the force field,the turbulence intensity and stress.In prelim-inary test studies the micron vortex structure of a submerged circular jet was visualized by SFSE method and SFME method with high resolution.The spatial resolution of the measurement rea-ches 1.125μm.Several vortex structures not yet reported were discovered.Experimental results show that the SFSE and SFME methods can get richer parameter information of the micron tur-bulent flow and the vortex flow field than other methods.Compared to other methods for flow field measurement,this method has the advantages of simple device,high spatial resolution,low requirements on the experimental conditions,intuitive display of the parameter information and suitability for measuring microscopic flow field.