Experimental and Numerical analysis of multi-port mini-channel evaporator
Speaker:Prof. Ming Li
Associate Professor
Department of Thermal Engineering
School of Automotive Engineering, Jilin University, China
Date & Time:20 Jun 2013 (Thursday) 15:00 - 16:00
Venue:HG01
Organized by:Department of Electromechanical Engineering

Abstract

There are more and more automotive air-conditioning evaporators use small extruded channels with passage diameters smaller than 1mm. Flow and heat transfer in mini-channels is of great interest in compact evaporator applications.

The heat transfer and pressure drop characteristics of several parallel mini-channel evaporators are investigated based on numerical simulation and experiments. The effects of different louvered fin structures such as fin pitch, louver pitch, louver angle, number of channels and diameter of mini-channels were investigated by simulations based on energy balance method. The results indicated that the performance of fins can be improved by decreasing the fin pitch. The overall performance of fins can be optimized in the condition of optimized louver pitch and louver angle, however, if the fin pitch is different, even the optimized louver angle is same, the optimized louver pitch is different. The heat transfer performance of the parallel evaporator can be improved by improving refrigerant mass flow rate, increasing the number of passages, and decreasing the mini-channel diameter, which will results in higher pressure drop in the refrigerant system. The flow uniformity was simulated for different tube ratio between passages, and the heat transfer performance whereof. The results indicated that there is no significant relation between the flow uniformity and heat transfer. However, the ratio of the tube passage would affect the heat transfer performance, i.e. there is an optimal ratio with which heat transfer quantity can be maximized which the pressure drop can be minimized.

Biography

Dr. Ming Li is an Associate Professor at the Department of Thermal Engineering of School of Automotive Engineering at Jilin University, China. His research interests are in the micro-channel and mini-channel heat exchanger that applied in automotive, and vehicle thermal management especially about the battery thermal management which applied in electric vehicle. He is deputy director of Department of Thermal Engineering, and senior member of Chinese Association of Refrigeration, and committee member of China Energy Society, and the secretary of the Heat Pump Association of Jilin province.