Aerodynamic Design And Performance Analysis Of A 7.5mw Supercritical Carbon Dioxide Radial Turbine

Supercritical carbon dioxide(S-CO2)power cycle system is simple,compact,efficient,flexible,and has strong primary energy adaptability.It can be combined with traditional thermal power,solar thermal power generation,new generation nuclear power and fuel cell waste heat utilization.In this paper,the design of a7.5MW supercritical carbon dioxide centripetal turbine and the research on its off-duty performance are of great significance to the realization of energy transition.First,carry out the theoretical design and optimization research of S-CO2 centripetal turbine.Based on MATLAB software,a turbine thermal and aerodynamic design program was developed,and the particle swarm optimization algorithm was introduced into the program to optimize the design parameters.Secondly,according to the design parameters,the turbine was designed in three dimensions;numerical simulation showed that the turbine power was 7.43 MW,efficiency was 84.81%,mass flow was 84.4kg/s,and the relative error between thermal design parameters and numerical simulation results was less than 3%,which verified the accuracy of the design method.Thirdly,the turbine flow is analyzed.In view of the small-scale eddy current problem at the rotor blade inlet,four optimization schemes were compared through numerical simulation,and the optimal scheme was finally determined.The efficiency reached 85.38%,the power reached 7.47 MW,the vortex size at the rotor blade inlet was reduced,and the overall flow The line is better.Finally,based on the numerical simulation,the performance of the S-CO2 radial turbine under off-design conditions is studied.The results show that when the inlet temperature,inlet pressure,outlet pressure and speed change by 10% respectively,except near the critical temperature,the influence of the inlet temperature change on the efficiency is between 0.5% and 0.7%;except that the inlet pressure is close to the outlet pressure,the inlet The influence of pressure change on efficiency is less than1.6%;the influence of outlet pressure change on efficiency is less than 0.4%;the influence of speed change on efficiency is less than 2.5%.The design of the turbine within a certain range can maintain high efficiency and power output,and has good performance in variable conditions.