封头结构对板翅式换热器流体分配性能的影响

摘要

Through an experimental system of flow distribution,a study on the flow distribution in platefin heat exchanger was begun.Experiment results show that the header configuration influences the flow maldistribution in plate-fin heat exchanger seriously.At the same time,experiment of influence for height of header on fluid flow maldistribution in plate-fin heat exchangers was carried out.The experiment results indicate that the higher header configuration is,the better the fluid flow distribution in plate-fin heat exchangers is.To describe the characteristics of header configuration,flow nonuniformity parameters were defined.The influences of different header configurations on flow allocation in plate-fin heat exchangers were experimentally studied.The experiment results indicate that the ratio of the maximum flow velocity to the minimum flow velocity of heat exchanger drops from 3-4 to 1.1-1.2 and the degree of flow nonuniformity reduces from 0.331 to 0.046.%研究了板翅式换热器封头高度与流体分配之间的关系,实验结果说明板翅式换热器的流体分配与封头高度有很大关系,封头高度越高流体分配就越均匀.引入不均匀参数,以便可以对流体在出口截面的分配特性进行研究,并进一步研究封头结构型式不同对于流体分配的影响,研究表明:换热器内部流体的流速的最大值与最小值的比值由3-4减少到1.1-1.2,其不均匀度也从原来的0.331减少到0.046.