摘要
利用粒子图像测速（PIV）技术，对胁在450～4490之间的16种工况下的二维后向台阶定常流动的流场进行观测，并与文献资料的结果和数值模拟的结果进行比较，得到在此胁范围内的台阶后再附着长度Xr随Re变化的规律，以及台阶后流速分布和水面线位置等特性，对实验过程中所出现的粒子跟随性问题和存在自由表面的问题进行了讨论。
In this paper,the velocity field of 2-D steady flow, with a free surface, over a backward-facing step, is measured with PIV （ particle image velocimetry） technology within the range of Reynolds number from 450 to 4490. Through comparison with data from reference papers and from nmnerical simulations, the rule for changing the re-attachment length Xr according to the Reynolds number,as well as the velocity distribution behind the step and the location of the free surface, are obtained. Furthermore, the main problems during the process of flow measurement, such as the trailing behaviors of particle tracers and the measurement of flow with a free surface, are discussed.
出处
《水利水电科技进展》
CSCD
北大核心
2008年第4期23-26,共4页
Advances in Science and Technology of Water Resources
关键词
后向台阶流
自由表面
流动测量
再附着长度
PIV系统
backward-facing step flow
free surface
flow measurement
re-attachment length
PIV system
