Numerical and experimental study of free convection through a horizontal open‐ended axisymmetric cavity

Abstract

This paper summarizes a numerical and experimental investigation of free convective heat transfer in an open‐ended cavity between two horizontal parallel circular plates. The upper plate is maintained at an ambient temperature and the lower one is heated. Air is used as the heat transfer medium. The numerical model equations are solved using a control volume‐based finite differences method, and the experimental study was performed using holographic interferometry. Streamlines and isotherm patterns are presented and discussed for different aspect ratios (A) and Rayleigh numbers (Ra). Heat transfer at the surface of the lower plate is thoroughly inspected in the ranges 0.1≤A≤1 and 102≤Ra≤5×106. Useful correlations of Nusselt numbers in terms of Ra and A are given with their validity ranges. Also, an investigation of both numerical and experimental results is performed. It shows similar temperature field aspect with some differences in the radial boundary layer thickness and a small deviation in the heat transfer.