Thermal analysis of radiation shields for space reactors using analytical and finite element methods

A finite element program (FEM) that uses a Newton-Raphson iteration and simplex elements has been developed to determine the temperature distribution in a multi-layered radiation shield with internal heating, temperature dependent thermal conductivities, and radiative boundary conditions. The temperature distribution in a 1-D slab shield using the FEM differed by less than 1% from the exact analytic solution for both adiabatic and isothermal front surface conditions. The temperature distribution in a 2-D shield with radiating surfaces at the top and back surface was also evaluated using the FEM. 9 figs