Numerical simulation of heat transfer and flow of cooling air in triangular wavy fin channels

NI Ming-long(倪明龙)^{1, 2}, CHEN Ya-ping(陈亚平)¹, DONG Cong(董聪)¹, WU Jia-feng(吴嘉峰)¹

(1. School of Energy and Environment, Southeast University, Nanjing 210096, China;
2. Jiangsu Electric Power Design Institute, Nanjing 211102, China)

Abstract:Numerical computation models of air cooling heat transfer and flow behaviors in triangular wavy fin channels (TWFC) were established with structural parameters of fins considered. The air side properties of heat transfer coefficient and pressure drop are displayed with variable structural parameters of fins and inlet velocities of cooling air. Within the range of simulation, TWFC has the best comprehensive performance when inlet velocity v_in=4-10 m/s. Compared with those of straight fins, the simulation results reveal that the triangular wavy fin channels are of higher heat transfer performances especially with the fin structural parameters of fin-height F_h=9.0 mm, fin-pitch F_p=2.5-3.0 mm, fin-wavelength λ=14.0-17.5 mm and fin-wave-amplitude A=1.0-1.2 mm. The correlations of both heat transfer factor and friction factor are presented, and the deviations from the experimental measurements are within 20%.

Key words:triangular wavy fins; heat transfer coefficients; pressure drops; plate-fin heat exchangers; air cooling