【摘要】 为区分激光多普勒稀态两相流动测量中出现的流体相信号和颗粒(气泡、液滴)相信号,本文提出可见度和基座的复合判别法,并设计了专用的信号预处理器,此预处理器能将原始多普勒信号分为两路,分别代表两相,并可用计数型信号处理器测量每路的速度及其它统计量。使用本方案对矩形管道內低速气泡-水两相流的实验和测量表明,对两相的区分和测量是成功的。文中给出了两相速度、湍流度和气泡滑移速度的测量结果。更多还原

【Abstract】 In this paper, a compound discrimination method has been proposed. It utilizes a combination of pedestal and visibility information embedded in each LDA burst to separate micro-paricle and large particle of dilute two-phase flow. According to this method, a preprocessor has been designed and built to carry out the discrimination. By using this pre-processor, initial signal flow originating from PMT of LDA can be processed and separated into two trains, each of which corresponds to one phase of the flow, and a counter type processor can be used in each train to measure velocities of the two phases as is usually done with single phase flow. The application of this system to the measurements and experiments of low velocity (Re about 8800) bubble-water flow shows that the separation and measurements are successful.更多还原