Quantification of Liquid Refrigerant Distribution in Parallel Flow Microchannel Heat Exchanger Using Infrared Thermography

This paper presents a method to quantify the distribution of liquid refrigerant mass flow rate in parallel flow microchannel heat exchanger from the infrared images. This method can be used for several types of heat exchangers: evaporators, condensers, gas-coolers and etc., also it can be applied to various heat exchanger designs: different inlet/outlet locations, different flow configurations and etc. After being implemented in a heat exchanger model, this method is validated against experimental data, and it is used to examine the validity of quality distribution function in operating heat exchangers. Also, heat exchanger model equipped with this method provides quantitative information of capacity degradation due to refrigerant maldistribution.