Entropy Generation, Heat Transfer of Water Near Density Inversion Region with Relative Positions of Hot and Cold Walls: Numerical Analysis

Abstract

This study investigates the entropy generation and heat transfer of water density inversion region in a square cavity with the different relative positions of hot and cold walls by numerical simulation. Mathematical models are solved using the EES (Engineering Equation Solver) program. A physical model is a 38 mm square cavity filled with water, with cold and hot wall temperatures maintained at 0oC and 10oC. Results indicated that the Nusselt number of cases 1 (cold and hot walls on both sides) is higher than case 2 (hot wall above, cold wall below) and case 3 (cold wall above, hot wall below) by 1.582 and 1.059 times, respectively. The average total generation per unit volume in case 1 increases by 1.577 times and 1.059 times, respectively, compared to cases 2 and 3, which almost correspondingly increase with heat transfer capacity. Entropy generation by fluid friction is negligible