Transient Natural Convection From Vertical Elements—Appreciable Thermal Capacity

Abstract

Natural convection transients are considered for laminar boundary-layer flow on vertical surfaces by the method previously presented by the present author. Cases are solved for elements having finite thermal capacity as, e.g., electric heaters or reactor elements. A wide range of thermal capacity is considered for fluid Prandtl numbers in the range 0.01 to 1000; for a step in internal energy generation rate. The Prandtl number effect is shown to be very small, in the generalized variables employed, and the range of thermal capacity which results in true convection transients is clearly delineated.