Decomposing Numerical Simulation and Experimental Verification of Carbon Dioxide Micro-channel Gas Cooler

Abstract

Abstract: 摘要：关键词： In order to investigate the effect of CO2 maldistribution in microchannel on the flow and heat transfer characteristics of gas cooler, decomposing numerical model of microchannel gas cooler in transcritical CO2 system was constructed and experimentally verified. The results show that the maximum flow rate nonuniformity decreases from 97% to 18% as total inlet flow rate of CO2 increases from 110 kg/h to 470 kg/h, meaning that the flow rate is the critical factor of maldistribution. The maldistribution of refrigerant flux has a significant effect on the flow characteristics of microchannel gas cooler. While to the heat transfer characteristics, its effect is not obvious. The numerical results were compared with the experimental data under different running conditions. The inaccuracy of average heat transfer coefficient ranges from 482% to 3825%, and the inaccuracy of friction coefficient ranges from 6.09% to 26.65%.

Key words: decomposing numerical simulation, microchannel gas cooler, carbon dioxide transcritical cycle, maldistribution

CLC Number:

TB 657.5

WU Jiang-Hong, LI Cheng, YANG Zhao-Guang. Decomposing Numerical Simulation and Experimental Verification of Carbon Dioxide Micro-channel Gas Cooler[J]. Journal of Shanghai Jiaotong University, 2012, 46(03): 474-479.

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