Abstract: To reduce the heat receiver mass,a mathematical and physical model of heat receiver for NASA 2 kW in space solar dynamic power system is formulated.The numerical simulations are performed and the effects of the structural and operational parameters on the heat receiver mass are analyzed.The results of the study indicate that structural parameters such as diameter,and number of the working fluid tube and,operational parameters such as compressor gas inlet temperature,rotating speed of the turbine and the recuperator effectiveness affect the heat receiver mass.Appropriate selection of these variables can distinctly reduce the weight of heat receiver.The calculated results can be used for the mass optimization of heat receiver.