CFD Analysis of Laminar Natural Convection from a Horizontal Circular Cylinder to its Concentric Elliptic Enclosure

Abstract

In the present paper, using a two-dimensional numerical simulation, the heat transfer from a hot circular cylinder to a cold vertical elliptic enclosure has been studied parametrically. The effect of ratio of cylinder radius to the half minor axis length of vertical elliptic enclosure (R ⁄b) on the rate of the heat transfer has been investigated for the Rayleigh number 10(4) and 10(5) . Governing equations have been solved using the finite volume method and TDMA in an ADI procedure. Results show that the patterns of streamlines, isotherms and the Nusselt number values depend strongly on Rayleigh number and ratio of R ⁄b. Furthermore, it is observed that by increasing the Rayleigh number and the ratio of R/b, the heat transfer rate is increased. For instance, when the ⁄ value is changed from 0.2 to 0.6 at Ra=10(5) , the Nusselt number is increased about 55 percent of its initial value. Also when the Raleigh number is risen from 10(4) to 10(5) at R ⁄b , the Nusselt number is climbed almost 65 percent of its initial value.