矩形窄缝通道内单相水流动特性研究

Research on Characteristics of Single-Phase Water Flow in Narrow Rectangular Channel

通过理论分析,得到了计算矩形窄缝通道单相层流摩阻系数的公式。对小高宽比矩形窄缝通道内的流动特性进行了实验研究,结果表明:矩形窄缝通道内单相摩阻系数随Re变化的曲线和圆管有相同的趋势,但圆管流动摩阻公式不适用于矩形窄缝通道。矩形通道内摩阻系数与Re和通道截面高宽比有关,通道高宽比越小,摩阻系数越大。实验结果和理论推导结论一致。从截面湿周和切向应力两方面解释了高宽比对矩形窄缝通道内单相水层流摩阻特性的影响机理。

A calculation formulation for laminar friction coefficient in narrow rectangular channel was obtained by theoretical analysis.Experiments have been made on flow characteristics in narrow rectangular channels with low aspect ratios,and the results show that the curve of friction coefficients in rectangular channel varying with Reynolds number is similar to that in round pipe.The conventional frictional correlations based on circular pipes are not available for rectangular channels,which depend on Reynolds numbers and aspect ratios,and the friction coefficient increases as the aspect ratio decreases.The experimental results agree well with the theoretical analysis.The effects of aspect ratios on frictional characteristics in laminar flow were explained by taking into account wetting perimeter and shear stress.