A novel configuration for heat transfer for a sphere based on constant wall temperature and heat flux

Abstract

The convective heat transfer from a sphere (10.2 cm diameter) to air is studied at different temperatures of sphere surface. The experiments were carried out by placing the sphere in an experimental channel (2.45x 0.48x 0.50 m). The velocity of air flow was changed by varying the orientation of the gate of the channel which has four levels. A fan of moderate capacity generates the air into the channel. The hollow copper sphere was heated by flowing hot water through it to obtain approximately constant wall temperature .In addition the sphere is heated by hot air to obtain a constant heat flux at different temperatures. The analytic solution for the steady heat transfer by conduction in a sphere with temperature dependent was obtained.