Natural Convection Heat Transfer Between Two Concentric Spheres

Huynh Nguyen Khang Le
NUS

Abstract
Natural convection heat transfer between two isothermal concentric spheres, the inner sphere is hotter, is investigated. The governing equations in two dimensional stream function-vorticity formulation are solved using finite difference explicit schemes: the fourth-order Runge-Kutta method is used for the vorticity transport equation and the energy equation and the Successive Over-Relaxation method for the stream function equation. The Prandtl number is kept constant at 0.7. The effects of the Rayleigh number on the flow patterns are studied with the Rayleigh number ranging from 10^2 to 10^6. The unsteady periodic flow patterns at Rayleigh number of 6.3×10^5 are discussed. These results are the first unsteady periodic results presented in literature