Although much attention has been paid to the supercritical CO2(S-CO2)Brayton cycle,there are still few works on the analysis and design of S-CO2 cycle tailored to the needs of the shipboard propulsion and power system.The primary purpose of this study is to carry out the thermodynamic design of a S-CO2 recompression Brayton cycle for shipboard application with 40MW output power.Particular efforts are devoted to a careful selection of the thermodynamic parameters of the cycle.The results show that the efficiency of the designed S-CO2 Brayton cycle with a relatively complex recuperation cycle is 45.06 percent,8.07 percent higher than that of a simple recuperation cycle.This indicates the great influence of the recuperation design on the efficiency of the Brayton cycle.Meanwhile,the compressor inlet pressure greatly affects the cycle efficiency,and the shunt flow percentage could partly reflect the cycle performance.This work is of important reference value for the development of future nuclear shipboard propulsion and power system.