Performance analysis and optimization of multiple compression brayton cycle for space nuclear system

With the rapid development of deep space exploration and space technology, the demand for energy used in space has gradually increased. For space energy systems, in addition to system efficiency, the mass of the whole system is also an important indicator to determine the launch cost and the feasibility of the design scheme. By using the Brayton cycle, the system of space nuclear energy can obtain higher energy conversion efficiency and more compact structure. In this paper, under the background of space nuclear energy, the mixture of Helium and Xenon was multiple compressed and split after the radiant radiator to reduce compressors consumption. Also, the cycle fluid was bled after the turbine directly entered the reactor for heating, so as to increase the inlet temperature of the reactor and reduce the total circulation heat absorption. After establishing the thermodynamic model and mass estimation model of the multiple compression system, the effects of bleeding ratio, number of compressors, pressure ratio, compressor inlet temperature and turbine inlet temperature on the thermal efficiency and mass of the Brayton system were studied. Then, taking thermal efficiency and total mass of the system as optimization objectives, the multiple compression Brayton system is optimized by genetic algorithm.