Numerical Study of Forced Convection Flow Around Rectangular Cylinders with Different Aspect Ratios

Abstract

The unsteady two-dimensional forced convection heat transfer and fluid flow around rectangular cylinders are investigated numerically. A range of Reynolds number between 100 to 200 and aspect ratios (H/D) 1, 2 and 3 are considered. In the present work, a fractional step finite volume code with staggered variables arrangement is used to solve Navier-Stokes and energy equations. A second order central differencing scheme is applied for both diffusion and convection terms. Time advancement is discretized using a second order implicit Cranck-Nicolson scheme. At the outlet of the domain the convective boundary condition is applied for the velocities and the temperature. The computed results of drag and lift coefficients, Strouhal number, mean recirculation length and Nusselt numbers of the square cylinder are found to be in good agreement with previous numerical results. Correlations between the cylinder Nusselt number and Reynolds number are presented for H/D= 2 and 3. In addition, a correlation of heat transfer is proposed as a function of Reynolds number and the aspect ratio (H/D)