Comparative Study on Cavitation Characteristics of Different Fuels Considering Thermal Effect in Injector Nozzle

Abstract

At present, facing the dual problems of world energy crisis and carbon emission pollution, the cavitation phenomenon formed in the nozzle due to the high pressure difference and whether the physical property difference of clean alternative fuels methanol and ammonia can be successfully applied and replace the traditional fuel has become the focus of current research. In this paper, the Schnerr-Sauer cavitation model considering the thermal effect of cavitation and the physical property parameters of fuel varying with temperature and pressure are embedded into the CFD software, and the cavitation characteristics of diesel, methanol and ammonia inside the nozzle are studied and compared. The results show that the influence of cavitation heat effect on diesel, methanol, and ammonia in the nozzle increases sequentially, manifested by the increase in the degree of cavitation in the nozzle; When the cavitation number is approximately 1.3 and 1.1, the fuel exhibits cavitation inception and supercavitation phenomena, respectively; The net temperature effect of fuel varies under different injection pressures, with diesel and methanol having a more significant heating effect in the nozzle flow, while ammonia has a more significant cooling effect when the injection pressure is less than 14MPa.