Investigating performance of new mini-channel evaporators

Abstract

In this paper, a new type mini-channel evaporator is proposed and studied experimentally. The evaporator is made of two parallel flow mini-channel heat exchangers connected with a return tank. The experiments are performed on psychrometric calorimeter test bench and the results are compared with test data of the conventional laminated evaporators and used to verify a simulation software. The comparisons show that the new mini-channel evaporator has advantages on volume (17.2% smaller), weight (2.8% lighter) and heat transfer (4.3% higher), but a little penalty on air and refrigerant side pressure drop. The test data have a good agreement with the simulation results using academic software. The effect of louver fin shape on performance is studied and the results show the louver fin with a flat top reduces the air side pressure drop while maintaining the same heat transfer rate as compared to mini-channel evaporator with the corrugated louver fin. The effect of refrigerant side arrangement on the evaporator performance is researched experimentally and the experimental results show that the two-pass flow arrangement is better for heat transfer and refrigerant side pressure drop reduction.