Establishment and verification of a two-phase flow distribution model in a parallel flow heat exchanger

doi:10.11949/j.issn.0438-1157.20171192

Abstract

Abstract:

The flow mal-distribution of the refrigerant will have great influence on the heat transfer performance of parallel flow heat exchanger. This paper presents a new two-phase flow distribution model for parallel flow heat exchanger based on the combination of T-junction model of T-tube, mass equation and pressure equation along the flow path as well as an appropriate algorithm to predict the distribution of parallel flow heat exchanger. The validity of the model is verified by the experimental data. It can provide a reasonable basis for the design of parallel flow heat exchanger. This paper calculates and analyzes the effect of quality and mass flow rate on the distribution of parallel flow heat exchanger. The results show that the quality has little influence on the distribution, and the flow distribution can be improved by increasing mass flow rate.

Key words: parallel flow heat exchanger, distribution characteristics, two-phase flow, numerical simulation, model

摘要：

制冷剂的分配不均对平行流换热器的换热性能会产生重大影响。基于T型管的T-junction模型，联立质量方程和压力方程，设计合适的算法建立平行流换热器两相流流量分配的模型，该模型的优势在于无需已知分歧管流量可模拟分歧管的分配特性。在此基础上，将模型的计算结果与实验数据对比验证，验证了模型有效性，为平行流换热器的设计提供合理的依据。计算并分析了干度与质量流量对平行流换热器分配的影响，结果表明干度对平行流换热器分配的影响不大。在干度不变时，提高流体的质量流量可以对平行流换热器流量分配进行改善。

关键词: 平行流换热器, 分配特性, 两相流, 数值模拟, 模型

CLC Number:

TB657.5

XU Xiaoxiao, XIAO Jiumin, CHEN Long, LIU Chao. Establishment and verification of a two-phase flow distribution model in a parallel flow heat exchanger[J]. CIESC Journal, 2018, 69(5): 1938-1945.

徐肖肖, 肖久旻, 陈龙, 刘朝. 平行流换热器两相流分配模型的建立与验证[J]. 化工学报, 2018, 69(5): 1938-1945.

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