格子板流道二维流场的激光测定与分析

为了考察在多层板中加有格子板对强化非均相分离过程的效应,用激光测速法对格子板流道中二维流场进行了测试.在非均相分离的工作范围内,选取了几种不同流速、不同高度的格子板进行了测试.测试结果发现,格子板流道存在三种截然不同的流动区域,即主流道内流速分布均匀的平行流区、格子板槽内以下部某一位置为中心的回转流区和两者交界处的混合流区,混合流区前部为尾流旋涡,后部为波动较大的混合流.在板高和板间距比为0.8～1.2的范围内,格子板流道的流场基本形式不变.

MEASUREMENT OF TWO DIMENSIONAL FLOW PATTERN OF FINNED CHANNEL WITH LASER DOPPLER ANEMOMETRY

In order to analyze the effect of additional fins on the multi-layer plate for heterogeneous mixture separation, the two dimensional flow pattern of the finned channel was measured with Laser Doppler Anemometry for different flow velocities and different heights of the fins. The study shows that the finned channel can be divided into three parts. The first part is the parallel flow region of uniform velocity distribution in the main channel. The second part is the circulating flow region in the pocket between two fins, with its centre in the lower part of the pocket. The third part is the mixed flow region between the main channel and the pocket, which consists of a front part of wake vortex and a back part of fluctuating mixed flow. When the ratio of the fin height to the fin-to-fin distance is 0. 8 to 1. 2, the basic feature of the flow pattern remains stable.