平行板叠末端交变流场的可视化实验研究

本文应用Particle Image Velocimetry(PIV)技术,对平行板叠后端交变流场进行了可视化实验研究。实验测得了在热声热机中加入板叠后,交变流动在平板末端涡旋的产生情况,分析了通道中心置轴线上速度分布曲线的变化。结果显示,随驱动比(为最大压力振幅与平均压力之比)的增加,板叠末端涡旋影响区域增大,其结构也由对称变为不对称;板叠末端形状为半圆形时涡旋形状变圆,板叠末端为三角形时涡旋被压扁而紧贴壁面。该研究对深入了解热声板叠术端附近流动状况与热交换之间的相互影响具有意义。

Measurement on oscillatory Flow at the End of the Parallel-Stacks Using Particle Image Velocimetry

The oscillatory flow field at the end of the parallel-stacks is visualized using Particle Image Velocimetry(PIV) measurement.The vortex shedding at the end of parallel-stacks in the engines was measured.The velocity distributions along the x-axis in the center of the channels are exhibited. The results show that the vortex influence area expands and the symmetrical vertex becomes nonsymmetrical, as the increasing of the drive ratio(Dr is the ratio of the pressure amplitude and the mean pressure).The plate end shape has evident influence on the vortex configuration.The vortex is circular around the circular end and is attached close to the plate at the triangular end.This work will be favor for the understanding of interaction between the oscillatory flow and the heat transfer at the end of the stacks.