Effect of Header Configuration on Refrigerant Distribution in Parallel Flow Microchannel Evaporators

doi:10.1007/s12204-019-2068-4

Abstract

Abstract: The refrigerant flow distribution in the parallel flow microchannel evaporators is experimentally investigated to study the effect of header configuration. Six different configurations are tested in the same evaporator by installing insertion device and partition plate in the header to ensure the consistency of the other structure parameters. The results show that the uniformity of refrigerant flow distribution and the heat transfer rate are greatly improved by reducing the sectional area of header. The heat transfer rate can increase by 67.93% by reducing the sectional area of both inlet and outlet headers. The uniformity of refrigerant flow distribution and the heat transfer rate become worse after installing the partition plate in the insertion devices and changing the inner structure of the header further.

Key words: refrigerant distribution| header| microchannel evaporator| two-phase flow

摘要： The refrigerant flow distribution in the parallel flow microchannel evaporators is experimentally investigated to study the effect of header configuration. Six different configurations are tested in the same evaporator by installing insertion device and partition plate in the header to ensure the consistency of the other structure parameters. The results show that the uniformity of refrigerant flow distribution and the heat transfer rate are greatly improved by reducing the sectional area of header. The heat transfer rate can increase by 67.93% by reducing the sectional area of both inlet and outlet headers. The uniformity of refrigerant flow distribution and the heat transfer rate become worse after installing the partition plate in the insertion devices and changing the inner structure of the header further.

关键词: refrigerant distribution| header| microchannel evaporator| two-phase flow

CLC Number:

TK 01

YU Dengjia (俞登佳), LIU Jinwei (刘金伟), Lü Hongbin (吕鸿斌), SHI Junye (施骏业), YOU Dian (游典), CHEN Jiangping* (陈江平). Effect of Header Configuration on Refrigerant Distribution in Parallel Flow Microchannel Evaporators[J]. Journal of Shanghai Jiao Tong University (Science), 2019, 24(3): 273-280.

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