Optimization of space radiators with step fins

The optimal design of the fin geometry of a heat pipe/fin radiator having fins with a step change in thickness, namely step fin (SF), has been performed in the present article. The optimization algorithm determines the thickness parameter describing the variation of fin thickness, intermediate fin length where the step change in thickness occurs, and the root thickness of the fins in order to provide the maximum heat radiated per element mass given the linear density of the heat pipe, the thermal conductivity and density of the fin material, the emissivity of the surface, and the operating temperature. The objective function is evaluated as the solution to a radiation thermal analysis problem performed using the Adomian decomposition method, which provides an analytical solution in the form of an infinite power series. The results of the new optimal design have been compared to heat pipe/fin radiators with flat fins (FFs). The results demonstrated that the maximum heat transfer rate per unit mass for a radiator with SF is always higher than that of a radiator with FF for the identical design condition.