NUMERICAL ANALYSIS ON HEAT TRANSFER AND FLOW RESISTANCE PERFORMANCES OF A HEAT EXCHANGER WITH NOVEL PERFORATED WAVY FINS

Abstract

The experimental and numerical studies of thermo-hydraulic characteristics of perforated wavy fin heat exchanger and unperforated wavy fin heat exchanger were conducted. Firstly, the two kinds of fins were studied under different air inlet velocity and constant inlet temperature. The results show that Nusselt number increases with Reynolds number and friction factor decreases with Reynolds number. Then, the performance of the two kinds of fins is numerically analyzed, and the simulation results are in good agreement with the experimental data. On this basis, the influence of different perforated fin parameters (fin height, H, fin pitch, s, wave amplitude, wa, perforation number, n, perforation diameter, d) on the thermal performance of wavy fin heat exchanger is discussed. It is indicated that friction factor and Nusselt number increase with increasing aperture, wave amplitude, fin pitch and perforation number or decreasing fin height under constant Reynolds number condition. Finally, the performance evaluation of heat exchangers with different parameters is carried out to obtain the best performance heat exchanger parameters, which can provide a reference for the design of the new wavy fin heat exchanger.