杆式防冲结构对管壳式热交换器性能的影响

传统防冲结构--防冲板因其结构简单、适用性强等优点应用非常广泛,但是防冲板的引入也带来了热交换器壳程压降增高以及热交换器综合性能系数降低等问题,通过对防冲结构进行改进以提高热交换器综合性能,减少其能耗损失具有重要意义。采用美国HEI设计中提到的防冲杆作为防冲结构,通过建立相应的物理模型,分别对加装防冲板和防冲杆作为防冲结构的管壳式热交换器进行数值模拟,比较2种不同防冲结构对壳程流场的影响。研究结果表明,在所研究的进口流速范围内,管壳式热交换器防冲杆结构相比于防冲板结构,壳程平均传热系数仅降低0.9%,壳程压降平均降低20.48%,综合性能系数提升23.35%。

Influence of Rod-type Anti-scour Structure on the Performance of Shell and Tube Heat Exchanger

The tradition anti-scour structure namely impingement plate,was widely used by its advantages of simple structure and strong applicability, however the introduction of impingement plate also brings about problems of the increasing of shell-side pressure drop and the reduction of comprehensive performance coefficient of heat exchanger. Therefore, it is of great significance to improve the comprehensive performance of heat exchanger and reduce its energy consumption loss by improving the anti-scour structure. The impact rod mentioned in the HEI design of the United States is used as the anti-scour structure. By establishing the corresponding physical model and numerical analysis of the shell and tube heat exchanger with anti impact structure, carried with impingement plate and anti-scour bar separately, to compare the effects of two different anti-scour structures on shell-side flow field. The results shows that in the range of inlet flow rates studied, for the shell and tube heat exchanger with rod-type anti-scour structure, the average heat transfer coefficient of shell side is only 0.9%, the pressure drop of shell side is 20.48% and the comprehensive performance coefficient is 23.35% higher than the impingement plate structure.