An Experimental Study on Natural Connective Heat Transfer from a Vertical Wavy Surface Heated at Convex/Concave Elements

Abstract

Natural convective heat transfer from a vertical wavy surface with discontinuous heating has been studied experimentally by considering the effect of heat conduction in unheated elements. The wavy surface is constructed with concave and convex semicircular cylinders and has discontinuous heat sources on concave or convex surfaces. The behavior of the flow and the temperature distributions in the boundary layer of surfaces have been discussed to clarify the effect of heat conduction in the unheated elements on local Nusselt number for the case of convex- or concave-heating. Empirical formulas have been derived to predict the average Nusselt number along the wavy surface.