Effect of thermal buoyancy on the flow through a vertical channel with a built-in circular cylinder

Abstract

The flow field and the temperature distribution around a heated / cooled circular cylinder placed in an insulated vertical channel are determined using a novel finite volume algorithm that combines some important features of the finite element methods with the finite difference based techniques. Elementwise interpolation ( isoparametric) and transformation of nonorthogonal element geometry into a square computational element have been made use of while solving for the integral conservation equations. An unsteady mixed convection situation has been considered for the study, and the effect of buoyancy on vortex shedding in the wake of a cylinder has been observed for a fixed Reynolds number of 100. Vortex shedding is found to stop completely at a critical Richardson number of 0.15. Below this critical value of the Richardson number, shedding of vortices into the stream is quite prominent. Heat transfer characteristics of the heated / cooled cylinder are studied as a function of Richardson number. The results are of use in the design of shell and tube heat exchangers.