Coating Effects on Transient Cooling a Hot Spherical Body

摘要

A numerical solution is carried out to treat the transient cooling problem with conduction and radiation for a hot spherical body covered with a cold coating material. The solution includes the equations of radiative transfer, coupled with a transient energy equation that contains both radiative and conductive terms. The radiative transfer equation was solved by the discrete ordinates method, and a parmetric study was performed by changing various physical parameters such as the optical thicknesses, thermal conductivity of the coating, emissivity, and diffu-sivity of the sphere. It was found that the properties of the coating have a direct effect on the cooling rate of the sphere.