Numerical Simulation of Turbulent Air Natural Convection in A U-Shaped Channel

Abstract

In this study a turbulent air-natural convection in a U-shaped channel under asymmetric heating conditions is investigated numerically. The heated channel comprises two insulated walls and two heated walls. One wall is directly heated at a constant temperature ranging from 50 to 500 °C, while the other wall is indirectly heated through thermal radiation emitted from the directly heated wall. The governing equations were solved using the Computational Fluid Dynamics (CFD) software, FLUENT. The temperature-dependent physical properties of the air were integrated using the “User Defined Functions”. The numerical results were validated against existing experimental data, showing a good agreement. Also, the impact of varying Directly Heated Wall (DHW) temperatures on parameters such as air temperature, air velocity, heat removal, and the Nusselt number has been examined. The findings offer valuable insights that can be used to optimize the design of natural convection systems across various applications.