An Improvement of Heat Exchanger Efficiency Using Zigzag Louver Fin

Abstract

Nowadays, Microchannel Heat Exchanger is widely used all over the world. It consist of tubes which have coolant flowing in for an exchange of heat and louver fins outside the tubes to enhance heat transfer. Changing the geometry of the louver fins is known to affect heat exchange behavior. This study focuses on an effect of 3 new zigzag patterns on louver fin surface to thermal efficiency of heat exchanger. Simulation of air flow over louver fins were performed by using commercial Computational Fluid Dynamics programme. The heat exchanger is made from Aluminum 3003. The inner surface temperature of the tube is constant at 10 ^oC. Air of which velocity is 5 m/s and temperature is 30 ^oC enters the heat exchanger and leave it to atmosphere.

From the result obtained, it was found that by making zigzag patterns on surface of louver fin results in an increase in heat transfer and pressure drop. Making too many zigzag patterns leads to an existence of vortex at exit of heat exchanger and therefore increases pressure drop. By comparing ratio of the increase in heat transfer to the increase in pressure drop resulted from using different zigzag patterns; it has been shown that zigzag louver fins with space between each zigzag give the highest efficiency.