Proposal and Thermodynamic Analysis of the Novel Solar Combined Brayton-Rankine Cycles for Space Power Generating

Due to the very low temperature and pressure and the high radiation intensity in the space, it could be possible to achieve Carnot efficiency in thermodynamic cycles. In this study, two new combined cycles including reheat regenerative Brayton, reheat regenerative Rankin and reheat regenerative Brayton with intercooling subsystems are investigated thermodynamically with Nitrogen, Hydrogen and Argon as working fluid. Due to the reduction of transportation costs, the weight of the space power generation systems is important. The results show that highest power to radiator area ratio belongs to Nitrogen Reheat Regenerative Brayton -Reheat Regenerative Rankine cycle without heat recovery heat exchanger as 0.912. Also, Hydrogen Intercooling Reheat Regenerative Brayton -Reheat Regenerative Rankine cycle has the highest thermal and exergy efficiencies of about 89%. The comparison results of Reheat Regenerative Brayton –Reheat Regenerative Rankine cycle with Intercooling Reheat Regenerative Brayton –Reheat Regenerative Rankine one show that the cycle with intercooling has the higher power generation, higher thermal and exergy efficiencies, lower exergy destruction and lower power to radiator area ratio.