Paper presented at the 5th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 1-4 July, 2007.
Steady laminar free convection in air from a row of parallel circular cylinders, is studied numerically. SIMPLE-C algorithm is used for the solution of the mass, momentum, and energy transfer governing equations. Simulations are performed for 10- cylinder assemblies with inter-cylinder spacings from 0.6 to 5 cylinder-diameters and Rayleigh numbers from 101 to 105. It is found that the thermal performance of the whole assembly increases as the Rayleigh number increases, and has a peak at an optimum separation distance among the cylinders which decreases with increasing the Rayleigh number.