Transient combined radiative and conductive heat transfer in plastics

Abstract

By the addition of metal and oxide particles to plastics, thermal transport properties, heat capacity, and density of polymers can be varied systematically. Radiation effects in a particle filled with various fillers become more important and transient temperature responses including radiation can be significantly different from those by conduction alone. Transient combined conduction–radiation heat transfer is analyzed in a non-gray layer of plastics, submitted to several thermal and radiative boundary conditions. The numerical method is an implicit finite difference procedure with nonuniform space and time increments. Coupling problems for the prescribed temperatures, prescribed radiative–conductive heat exchange laws, and mixed kind thermal boundary conditions are worked out for opaque as well as vitreous interfaces with specular reflections. Solutions are given to demonstrate the effect of different parameters, such as radiation–conduction parameter, radiation–convection parameter, and emissivity of the surfaces on temperature distribution and heat flux profiles across the layer. J. VINYL. ADDIT. TECHNOL., 11:28–37, 2005. © 2005 Society of Plastics Engineers