绕管式换热器单相流计算方法及实验对比

Calculation method and experimental comparison of single-phase flow in spiral-wound heat exchanger

为了绕管式换热器的准确设计计算,针对Schmidt和Gilli关于绕管式换热器单相流的管程和壳程的对流换热及流动压降的计算关联式,文中通过实验及理论分析,给出了修正关联式。制作了一台按照典型绕管换热器结构设计的试件,用于水-水对流换热实验,得到了分别改变管程水速和壳程水速的传热系数图和流动压降图。通过Schmidt和Gilli公式的计算值与实验值的对比,采纳了Schmidt关于管程对流换热的计算关联式,对壳程对流换热计算关联式以及管程和壳程的流动压降计算关联式进行了改进。改进后的计算关联式进行计算后的传热系数及流动压降与实验数据吻合较好。

For more accurate design and calculation of spiral-wound heat exchangers,this study,based on experimental investigations and theoretical analysis,presented a correction for the correlations of convective heat transfer and flow pressure drop given by Schmidt and Gilli for the single-phase flow in both tube side and shell side.A typical spiral-wound heat exchanger was designed and made for the experiments of water-to-water convective heat transfer.Variation patterns of the convective heat transfer and the flow pressure drop were obtained by changing the water flow velocity of tube side and shell side,respectively.By comparing the calculated data of Schmidt and Gilli correlations with the experimental results,Schmidt correlations for the tube-side convective heat transfer are validated and adopted,while the correlations for the shell-side convective heat transfer and the flow pressure drop of both sides are revised and improved,accordingly.The improved correlations show better agreement with the experimental data.