应用二维激光测速系统研究面流消能的紊动特性

本文应用二维激光测速系统对面流消能工下游典型流态的紊动特性进行了系统的试验研究,得到了不同来流条件下面流的时均流速、紊动强度及雷诺应力等沿主流与回流区的分布特征;计算并绘制了流线图,由此分析了淹没面流时底旋滚长度和佛劳德数的关系。对紊动能量的转换过程及耗散特征进行了计算分析,初步探明了消能机理。

EXPERIMENTAL STUDY ON TURBULENT CHARACTERISTICS UNDER BUCKET ENERGY DISSIPATORS BY USING A 2-D LDA SYSTEM

Turbulence measurements downstream of an energy dissipators, including the rever.se flow region were performed using a two-dimensional Laser Doppler Anemometer (2-D LDA). The mean velocity distributions, turbulence intensities and Reynolds shear stresses were revealed in and around the separated shear layer and recirculation region. The patterns of the streamlines were calculated and drawn, and then, the reattachtnent properties were stu-died varying with Froude numbers. Finally, the transition process of turbulent energy and energy dissipation were analysed, the mechanium of energy dissipation was tentatively explained.