Natural convection heat transfer between an eccentric circular cylinder inside a tilted square enclosure

Abstract

A numerical study of two-dimensional steady natural convection is performed for a uniform heat source applied on the inner circular cylinder in a square air-filled enclosure in which all boundaries are assumed to be isothermal. The developed mathematical model is governed by the Governing equations of continuity, momentum and energy. The effects of vertical cylinder locations and Rayleigh numbers on fluid flow and heat transfer performance are investigated. Rayleigh number is varied from 103 to 106 and the location of the inner cylinder is changed vertically along the centerline of the enclosure from an eccentricity of −0.5 to 0.5 upward and downward, respectively. It is found that at small Rayleigh numbers does not have much influence on the flow field while at high Rayleigh numbers have considerable effect on the flow pattern. In addition, the total average Nusselt number behaves nonlinearly as a function of locations. Results are presented in terms of the streamlines, isotherms, local and average Nusselt numbers. The number, size and formation of the cell strongly depend on the Rayleigh number and the position of the inner circular cylinder. Detailed results of the numerical has been compared with literature ones, and it gives a reliable agreement.