Computational Fluid Dynamic Simulation Analysis of Effect of Microchannel Geometry on Thermal and Hydraulic Performances of Micro Channel Heat Exchanger

Abstract

Micro Channel Heat Exchanger (MCHE) is one of the micro-scale equipment designed for higher efficiency in heat transfer. Among many factors, heat transfer rate and pressure drop are the most important considerations for performance of MCHE. Geometry of microchannel has significant impact to the heat transfer performance of refrigerant. In practice, rectangular and circular microchannel are most commonly used in the industry. To accurately and efficiently analyze the effect of microchannel geometry, heat transfer between refrigerant flow and air flow in segmental MCHE was modeled using Computational Fluid Dynamics (CFD) simulation. The data input for this study was obtained from the previous work which studied on the header part of automotive R134a microchannel condenser. This study was carried out to continue the previous simulation which focus on MCHE distributor. The overall performance that include both thermal and hydraulic were analyzed and compared between rectangular and circular MCHE. Parametric study to optimize the performance of MCHE was carried out to analyze effect of refrigerant velocity to the overall performance of MCHE.