燃料串/并联的航空SOFC-GT混合系统性能对比分析

When the solid oxide fuel cell − gas turbine(SOFC−GT)hybrid system is used as the power source for electric propulsion aircraft,it faces low−temperature and low−pressure atmospheric environment and has strict weight requirements. Therefore,optimizing the system configuration to make the hybrid system satisfy the aviation applications is an effective way to solve the problems. In this paper,two configurations of SOFC−GT hybrid system with fuel in parallel and series are proposed,and they are compared and analysed in terms of thermal cycle theory,system thermodynamic performance and power−to−weight ratio. The results show that the thermodynamic performance of the parallel system is better than that of the series system. The electrical efficiency, specific work and power−to−weight ratio increase by 3.32%,113.14% and 34.04%,respectively,and the CO₂ emission rate is reduced by 3.22%. With the increase of the pressure ratio,the efficiency of the series system has an optimal value,while with the increase of the combustor temperature,the efficiency of the parallel system continues to decline. In the range of 4~6 of the ratio of air to fuel,the output power of the series system changes more obviously,which is 116.29%~87.11% compared with the parallel system. In addition,although the power−to− weight ratio of the SOFC−GT hybrid system is relatively low,it is better than the lithium battery in terms of energy density based on its excellent efficiency,which is conducive to improving the performance of electric propulsion aircraft.