【摘要】 通过折射率匹配方法 ,应用激光多普勒测速仪测量了突缩与分叉复合管内的液体流场 .采用石英玻璃制作实验段 ,苯甲醇和乙醇的混合溶液作为流动工质 ,适当调配两种溶液的混合比例 ,使液体工质和固体壁面具有相同的折射率 ,均为 1 4 5 8,消除了壁面对测量光线的折射影响 ,拓宽了激光多普勒测速仪的应用范围 ,提高了测量精度 .测量结果表明 ,在汇流区域的下游 ,在两根管道轴线组成的水平面内 ,主流速度分布呈双峰状 ,其中较大的峰值偏向主管中正对旁路的壁面一侧 .在铅垂平面内 ,轴向速度分布呈“M”型 .更多还原

【Abstract】 Liquid flow field in a tube with a combination of a stenosis and a bifurcation was measured using refractive index matching technique.Test section was made of quartz glass tube with a refractive index of 1.458,meanwhile,a mixture of 54% benzyl alcohol and 46% ethyl alcohol with the same refractive index as that of quartz glass was chosen as working fluid,so that the effect of refraction on the tube wall was successfully eliminated. Velocity profiles upstream and downstream the bifurcation were measured with a laser Doppler anemometer(LDA),and a skewed double-peak velocity distribution was found downstream the bifurcation. Although similar data could be found in the literature, the ones from present measurements are more complete and accurate.更多还原