板翅式换热器结构优化及其性能数值模拟

1. 中国石油大学(华东)储运与建筑工程学院;2. 中国船舶重工集团公司第七二五研究所· 海洋腐蚀与防护国家重点实验室

LNG;板翅式换热器;流量分配;理论模型;数值计算;结构优化

Structure optimization and performance numerical simulation of plate-fin heat exchanger
CAO Xuewen1, SHI Qian1, PENG Wenshan2

1. College of Pipeline and Civil Engineering, China University of Petroleum (East China);2. CSIC Luoyang Ship Material Research Institute//State Key Laboratory for Marine Corrosion and Protection

LNG, plate-fin heat exchanger, flow distribution, theoretical model, numerical simulation, structure optimization

备注

板翅式换热器内部纵横两个维度的流量分配不均,导致其换热性能降低。基于单相流量分配理论和板翅式换热器内部流场特性,通过改变换热器进出口管个数、进出口方式、端部入口管相对位置等,建立了新型板翅式换热器结构。基于CFD 方法的Fluent 数值计算方法,对板翅式换热器优化前后的流量分配特性进行数值模拟,研究优化后的端部入口管相对位置、入口管个数及出口管个数对流量分配的影响规律。结果 表明:改变进出口方式可以均衡各通道路径在入口和出口处的总压降,有效改善板翅式换热器的流量分配特性;优化后的板翅式换热器最佳参数组合是端部入口管相对位置为0.033、入口管个数为5、出口管个数为1,该结构可以使气相和液相的流量不均匀度降低约50%,对提高换热器换热性能具有重要意义。(图 10表1,参[25]

The flow distribution in vertical and lateral dimensions inside the plate-fin heat exchanger is not uniform, leading to the deterioration of its heat transfer performance. In this paper, a novel structure of plate-fin heat exchanger was constructed by changing the number of inlet and outlet pipes, the inlet and outlet modes and the relative position of the inlet pipe at the end, based on the single-phase flow distribution theory and the flow field characteristics inside plate-fin heat exchanger. Then, the flow distribution characteristics before and after the optimization of plate-fin heat exchanger were numerically simulated by means of the Fluent numerical calculation based on CFD method. Finally, the effecting laws on the flow distribution by the relative position of the inlet pipe, the number of inlet pipes and the number of outlet pipes after the optimization were studied. It is shown that changing inlet and outlet modes can balance the total pressure drop of all paths at inlets and outlets, so as to effectively improve the flow distribution characteristics of plate-fin heat exchanger. In addition, the optimal structure parameter combination of the optimized plate-fin heat exchanger is the relative position of the inlet pipe at the end of 0.033, 5 inlet pipes and 1 outlet pipes, which can decrease the nonuniformity of gas and liquid flow by 50% or so. The research results are of great significance to enhance the heat transfer performance of heat exchangers. (10 Figures, 1 Table, 25 References)