Optimum size and location of diamond shaped isotherm blocks in heat transfer and friction of flow in a channel

Abstract

In this paper, fluid flow and heat transfer characteristics in a channel equipped with two isothermal diamond blocks such as blocks filled with PCM’s (during phase changing) to find out the optimum state in fluid flow and heat transfer behavior have been investigated. Different Reynolds and Prandtl numbers and different geometrical parameters such as the block size and location have been studied. The governing equations, including continuity, momentum, and energy, have been solved by the SIMPLE method. Results show that an increase in the block size and an increase in the distance of the blocks from the walls of the channel increases the friction factor and bulk temperature changing. Also, the ratio of the bulk temperature changes to friction factor for different Reynolds and Prandtl numbers shows an optimum state at a = 0.11 and 0.125 < b < 0.15. The results of this study could be used in designing air-conditioning systems or in microchannels equipped by blocks or ribs to enhance the heat transfer rate.