Enhancement of Heat Transfer and Heat Exchanger Effectiveness in a Double Pipe Heat Exchanger Filled with Porous Media: Numerical Simulation and Sensitivity Analysis of Turbulent Fluid Flow

Abstract

A 2-D numerical simulation and sensitivity analysis are carried out on turbulent heat transfer and heat exchanger effectiveness enhancement in a double pipe heat exchanger filled with porous media. The Darcy–Brinkman–Forchheimer and the k–ε turbulent models are employed to achieve heat transfer and heat exchanger effectiveness in the presented model. The sundry parameters Reynolds number (3000 ≤ Re ≤ 5000), Darcy number (10-5 ≤ Da ≤ 10-3) and the porous substrate thickness (1/3 ≤ δ ≤ 1) are studied. It is found that the mean Nusselt number increases by increasing the values of Reynolds number and dwindling of the Darcy number and porous substrate thickness. In addition, the heat exchanger effectiveness enhances with the Re and Da numbers and δ. The sensitivity analysis revealed that to maximize only the mean Nusselt number then it can be achieved for Re=5000, Da=10-5 and δ=1/3. However, to maximize only the heat exchanger effectiveness then it attains at Re=5000, Da=10-3 and δ =1. On the other hand, to maximize Nu and E simultaneously, then it can be obtained for Re=5000, Da=10-5 and δ=1.