换热器各流路对壳侧气液两相流动特性的影响

针对工业中广泛应用的管壳式换热器，应用空气-水两相混合物实验研究了壳侧旁路，泄漏流对气液两相流体流动特性的影响，以Ishihara两相流动模型为基础，建立了以横掠管束的主流路为基础的错流区通用两相压降计算关联式，通过错流区，泄漏流的分相流动模型，分析计算了主流路，旁路，泄漏流中气液分布，也分析了泄漏流对壳侧单相，两相总流量在各个分流路的流量分配影响，研究表明，主流路和旁路中气液各自占相应总流量的比例在不同的流型下明显不同，且比例值的波动范围较大，气液流量的分布在壳侧是不均匀的，折流板/换热管之间的泄漏流对壳侧的两相流动特性影响较小，而折流板/壳体之间的泄漏流影响较大。

The Effects of Each Flow Stream upon Gas-Liquid Two-Phase Flow Characteristics in the Shell-Side of a Shell-and-Tube Heat Exchanger

The experimental research was carried out on the effects of bypass and leakage flow streams upon the shell|side flow characteristics of two|phase flow on the horizontal shell|and|tube heat exchanger (TEMA|E type), widely applying in industry, with vertically cut baffles. General correlations of two|phase pressure drop in the cross|zone were proposed on the basis of main flow stream by using Ishihara two|phase flow model. The predicted values of the correlations agree with the experimental data well. The gas|liquid distributions in the main, bypass and leakage flow streams were analyzed and calculated by using divided|flow model. The gas and liquid percentages of B, C, A and A+E streams were obtained. It is founded that the percentages are dependent on the two|phase flow patterns, and have wide fluctuation ranges. The leakage of baffle/tube has little effect on the two|phase flow characteristics in shell|side but the leakage of baffle/shell has a great effect.