Abstract: This research established the geometric models of the Shell-side of plate and shell heat exchanger(PSHE). Numerical simulations calculated the deviations and the relative standard deviation of the mass flow, the fluid flow distribution performances were analyzed, the influences of fluid flow distribution performance on heat transfer efficiency, pressure drop and effectiveness of PSHE were analyzed. To optimize the design, a head and circular shaped stripe plate installed at the entrance could improve the impacts of fluid flow distribution and improve the performances of plate and shell heat exchanger. It was concluded that the uneven fluid flow distribution on the shell-side of plate and shell heat exchanger could significantly decrease the whole performances and increase the pressure drop, while it had little effects on the heat transfer efficiency, with the offset of the total heat exchange capacity less than 3%. Moreover, the optimization design not only improved the distribution uniformity obviously, but also made the drop of effectiveness and pressure drop less significant.

Key words: plate and shell heat exchanger(PSHE), fluid flow distribution, heat exchange, numerical simulation, optimization design

摘要： 以一种板壳式换热器壳程为研究对象,建立了几何模型并进行了数值模拟,通过对各流道的流量偏差和相对标准差的计算,分析了壳程物流分配的特性,并总结了物流分配特性对换热器的传热效率、整体效能以及压降的影响。模拟与分析结果显示:换热器壳程存在严重的物流分配不均匀现象,这种现象会造成换热器整体效能的下降,同时造成压降的大幅升高,但是对于传热效率的影响很小,总换热量偏移不足3%。为了改善物流分配带来的影响,提高换热器的性能,通过在入口处设置封头和圆弧状条纹板对换热器壳程来进行优化设计。优化分析结果表明:该设计可以改善换热器物流分配不均匀性,并能使换热器效能下降明显降低,压降相对减小,可以为板壳式换热器的优化提供参考。

关键词: 板壳式换热器, 物流分配, 传热, 数值模拟, 优化设计