Air-Side Performance Characterization of Air-to-Refrigerant Heat Exchangers Using Parallel Parameterized CFD

Abstract

The goal of the study presented in this paper is to use Computational Fluid Dynamics (CFD) to characterize the heat transfer and friction performance of fins used in air-to-refrigerant heat exchangers. Five different types of fins used in air-cooled heat exchangers (HXs) are studied using Parallel Parameterized CFD (PPCFD) approach described in this paper. The fin types considered in this paper are; Plain, Wavy, Slit, Super Slit, and Louver. 3-D CFD models are built and tested for these fin types. Based on the CFD results, air side heat transfer coefficient (HTC), Colburn j factor, Fanning f factor, and pressure drop are calculated. The results from CFD simulations are compared against experimental data from the literature for the different fin types and a good agreement is found between the two. In addition, the results from CFD simulations are used to evaluate the thermal and hydraulic performance for a wide range of heat exchanger parameters such as tube diameters, fin pitch, number of rows, and frontal air velocity. The results show the advantages of using PPCFD to efficiently develop correlations for different types of fins used in air-cooled HX, with significant reduction in engineering time. The PPCFD approach can be extended to efficiently optimize novel heat transfer surfaces.