Effect of Thermal Resistance in a Sphere on Apparent Convective Heat Transfer Coefficient

摘要

The apparent convective heat transfer coefficient between a spherical particle and a surrounding fluid was investigated by the techniques of numerical analysis and dimensional analysis in case of a considerable heat transfer resistance in the particle.The ratio of the apparent Nusselt number, Nu' to the true Nusselt number, Nu, was found to be related with Biot number, Bi, by the following equation.(Nu')/(Nu)=(1)/(n centre dot Bi + 1)In this equation, the value of n was as follows; (1) n was 0.2 in case of a constant heat flux between the particle and the fluid, and (2) n varied with Bi number in case of a constant fluid temperature.