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采用计算流体力学方法对螺旋隔板套管式换热器壳侧的传热和阻力特性进行模拟,建立了螺旋升角为40o、螺旋隔板高度分别为b,3b/4,b/2,b/4和b/8(b为螺距)的换热器模型,分析了螺旋隔板高度对壳程流体传热的影响.结果表明,相同壳程工质体积流量下,换热器的壳程总换热量、换热系数和阻力系数随隔板高度增加而增加,单位长度压降随隔板高度增加而减小.隔板高度为b,3b/4和b/2时比隔板高度为b/8时的换热系数分别提高7.83,3.68和3倍,壳程进出口压降分别减少98%,97%和95%,但阻力系数却分别提高34,15.3和5.3倍.为提高螺旋隔板强化单管换热器的壳侧综合换热性能,其隔板高度应为1/2b～3/4b.
The heat transfer and resistance characteristics of the shell side of spiral baffle bushing heat exchanger were simulated by computational fluid dynamics (CFD). The helix angle was 40o, the baffle height was b, 3b / 4, b / 2, b / 4 and b / 8 (b is the pitch), the influence of height of helical baffle on the heat transfer of the shell fluid is analyzed.The results show that under the same shell fluid flow rate, the heat exchanger shell The total heat exchange capacity, heat transfer coefficient and drag coefficient increase with the height of the baffle, and the pressure drop per unit length decreases with the height of the baffle.When the baffle height is b, 3b / 4 and b / 2, The heat transfer coefficient increased by 7.83, 3.68 and 3 times respectively when the height was b / 8, and decreased by 98%, 97% and 95% respectively, but the resistance coefficient increased by 34,15.3 and 5.3 times respectively. Improve the spiral shell reinforced single tube heat exchanger shell side of the comprehensive heat transfer performance, the partition height should be 1 / 2b ~ 3 / 4b.