MPC轴流管壳式换热器的壳程局部传热性能

对一种具有并流多通道进出口结构(MPC)的轴流管壳式换热器的壳程局部传热性能进行实验研究,分别在有壳程进口段分布挡板与无分布挡板的情况下,探讨了进口段局部表面传质努塞尔数的分布、局部平均表面努塞尔数与管束位置及雷诺数的关系,分析了进口段和换热器整体的平均传质努塞尔数与雷诺数的变化关系,揭示了壳程进口段的局部表面努塞尔数的分布规律,并进行了机理分析.研究结果表明,分布挡板能够有效促进壳程流场的分布,提高换热器壳程的整体传热性能.

Local Heat Transfer Performance of Shell Side of Axial-Flow Shell-and-Tube Heat Exchanger with MPC

In this paper, the local heat transfer performance of the shell side of an axial-flow shell-and-tube heat exchanger with multi-parallel-channel inlet/outlet (MPC) was experimentally studied, with or without distributed baffles being set in the inlet region at the shell side. The investigation includes such aspects as (1) the distribution of local surface Nusselt number (Nu) in the inlet region;(2) the correlation between the local-mean surface Nusselt number and the tube bundle location as well as the Reynolds number (Re);(3) the variations of mean Nusselt number and Reynolds number of the inlet region and the heat exchanger;(4) the distribution rule of the local surface Nusselt number of the inlet region at the shell side;and (5) a reasonable mechanism analysis of the above-mentioned statements. The results indicate that distributed baffles effectively improve the fluid flow distribution and enhance the overall heat transfer performance of the shell side of the heat exchange.