Paper Title
Numerical Simulation of Natural Convection in Air Layers with Two Discrete Heaters

Abstract
A numerical study on natural convection in rectangular air cavities with two discrete heaters was carried out to solve the governing equations bassed on the finite difference technique developed by Patankar. The numerical solution covers cases of natural convection for Prandtl number, Pr = 0.72, Rayleigh number ranging from 102 ≤ Ra ≤ 107, and cavity inclination angle, Φ from 0o to 180o with different aspect ratios, 0.5 ≤ A ≤ 50. The effects of heaters position ratio, B1 and B2, and heaters size ratio, 0.125 ≤ ε ≤ 0.375 were studied. The calculation grid used in the solution was tested to determine the best grid spacing and the effects of grid size on the numerical solution. The results are presented graphically in the form of streamline and isotherm contour plots. The heat transfer characteristics, local and average Nusselt number are presented and compared with previous results and good agreement was found. Keywords - Numerical Simulation; Natural convection; Air cavities; Discrete heating; Rectangular layers