Study of heat transfer and efficiency of circular porous fins under fully wet conditions

فاقد چكيده فارسي

Abstract Fins are extending surfaces that are widely used to increase the rate of heat transfer, because they increase the heat transfer surface. The concept of using fins made of porous materials with introducing the Darcy model is fistly introduces by Kiwan et al. The present work investigates the temperature distribution, heat transfer and efficiency of circular porous fins with rectangular section in fully wet conditions. Fins are made of aluminum and the tips of fins are insulated. Furthermore, it is assumed that the heat transfer coefficient depends on temperature and in the fin it changes according to temperature changes. In order to derive the heat transfer equation, energy balance and Darcy model are used. After present in the governing equation to obtain the temperature distribution, Gauss-Seidel method is applied. After that, effects of porosity, Darcy number, Rayleigh number and relative humidity on fin efficiency are examined. The results showed that by increasing the porosity, the Darcy number, the Rayleigh number, the fin efficiency increases.