Experimental study of the natural convection flow around an array of heated horizontal cylinders

Natural convection heat transfer from an array of heated cylinders has recently attracted much attention. However, in almost all of the investigations, attention has been restricted to the influence of geometrical parameters on the overall heat transfer. The present work deals with an experimental study of natural convection flow from a vertical array of two heated horizontal cylinders. A detailed analysis of the local temperature and velocity fields is performed. 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 that are obtained for a variety of combinations of spacings and Rayleigh numbers are compared with known numerical results. The comparison shows a satisfactory agreement.