Multi-objective optimization of endoreversible magnetohydrodynamic cycle

Abstract

According to the magnetohydrodynamic cycle model established in the previous literature, this article applies finite time thermodynamic theory and NSGA-II algorithm to conduct multi-objective optimization by taking heat exchanger thermal conductance distribution and isentropic temperature ratio of working fluid in the compressor as the optimization variables, and taking power output, thermal efficiency, ecological function and efficient power as objective functions. Through numerical work, single-, bi-, tri- and quadru-objective optimizations with different combinations of the optimization objectives are performed. The results show that when the four-objective optimization is carried out with power output, thermal efficiency, ecological function and efficient power as the optimization objectives, the deviation indexes of the three decision-making ways is the same as 0.971, which is less than other multi-objective optimization results, and less than the deviation indexes (0.1622, 0.8767, 0.1031, 0.0973) obtained by single-objective optimizations under the conditions of maximum power output, maximum thermal efficiency, maximum ecological function and maximum efficient power, respectively. At this time, the design scheme is more in line with the ideal scheme.

Keywords

• Endoreversible MHD cycle
• Finite time thermodynamics
• Power output
• Thermal efficiency
• Ecological function
• Efficient power