Influence of fuel reforming with low water to carbon ratio on thermodynamic performance of aviation solid oxide fuel cell - gas turbine hybrid system

Abstract

In this paper, a novel aviation solid oxide fuel cell-gas turbine (SOFC-GT) hybrid system based on n-decane reforming with low water to carbon ratio (S/C) is studied. The system not only improves the power generation performance but also reduces the weight penalty caused by the large demand for water in fuel reforming process. Therefore, by establishing the system model, the effects of reforming parameters on the performance of reforming, SOFC and the system at low S/C are analyzed in turn. And the safe range of reforming parameters is determined by taking carbon formation, excessive temperature gradient and temperature of SOFC as the safety boundary. The results show that high S/C, oxygen to carbon ratio (O/C) and reforming temperature inhibit carbon formation. The SOFC temperature gradient is affected by SOFC efficiency and excess air ratio. Therefore, changing reforming temperature or substance ratio is an effective way to reduce the SOFC temperature gradient. When the reforming temperature is 1023 K, the area of safety region reaches the maximum within the substance ratio studied. The S/C has little effect on system efficiency, while low O/C and high reforming temperature effectively improve system efficiency, but it also increases the size of air preheater significantly.