Numerical study of the laminar natural convection flow around an array of two horizontal isothermal cylinders

Natural convection heat transfer from an array of heated cylinders has rece ived attention in recent years. However, most of the previous investigation s has been experimental and has been restricted to the influence of geometr ical parameters on the overall heat transfer. The present work is devoted t o the numerical study of laminar natural convection flow from an array of t wo horizontal isothermal cylinders. This work, that enters within the frame work of general study dealing with an array of several cylinders, states th e problem in Cartesian coordinates system, involves the use of a control-vo lume method and solves the full vorticity transport equation together with the stream function and energy equations. The modifications of the average Nusselt number evolution compared with the single cylinder are explained in terms of velocity and temperature fields of the flow around the cylinders. Results are obtained for variety of combinations of spacing and numbers of Rayleigh. (C) 1999 Elsevier Science Ltd.