THE NON-FOURIER EFFECT ON THE FIN PERFORMANCE UNDER PERIODIC THERMAL CONDITIONS

This paper investigates the effect of thermal relaxation time (the non -Fourier effect) on the thermal performance of a convective fin under periodic thermal conditions. The environment heat transfer coefficient is assumed to be spatially varying. The periodic oscillation of the b ase temperature is considered. An efficient numerical scheme involving the hybrid application of the Laplace transform and control volume me thods in conjunction with hyperbolic shape functions is used to solve the linear hyperbolic heat conduction equation. The thermal performanc e of the fin predicted by using the non-Fourier heat conduction model is compared with that predicted by using the Fourier model. Results sh ow that the effects of the thermal relaxation time on the fin performa nce are significant for a short time after the initial transient. For the steady state, the non-Fourier effect is still great if the frequen cy of the temperature oscillation is high. (C) 1998 Elsevier Science I nc. All rights reserved.