Abstract: |
Aiming at the problem of insufficient energy efficiency of space nuclear power supply in deep space exploration missions, combined with the Brayton cycle and organic Rankine cycle, N2O was developed as the top cycle working medium, and the organic Rankine cycle (the bottom cycle) was used to further recover the waste heat of the system. By establishing a mathematical model of the combined system, the influences of the shunt ratio, inlet pressure and temperature of the top cycle turbine on the thermodynamic performance, specific mass and exergoeconomics performance of the system are studied. Genetic algorithm based multiobjective optimization is used to obtain the Pareto solution for the key performance indicators. The results reveal that the thermal efficiency of the coupled system is increased by about 7.7% compared with the single top system. Finally, through the multiobjective optimization method, Pareto solutions can be found, which provides a theoretical basis for the high efficiency space nuclear power system design and optimization. |