Combustion characteristics of RP-3 aviation kerosene/n-butanol blended fuel in a compression ignition engine

In order to meet the requirements of Sustainable Aviation Fuel (SAF) to achieve the imperatives of energy conservation and emission reduction. This paper compares the combustion characteristics of diesel, RP-3/n-butanol blends in terms of heat release rate, in-cylinder pressure, temperature and fuel economy in a compression ignition engine, taking into account the advantages of lightweight structure, low fuel consumption and wide range of applications of aviation piston engines. The results certified the viability of applying RP-3 and RP-3/n-butanol blends in diesel engines. Adding n-butanol prolonged the ignition delay and shorten the combustion duration. Moreover, the peak of the pressure, temperature and apparent heat release rate (AHRR) increased. In addition, the blended fuel showed obvious diffusion combustion characteristics at high load. With the n-butanol increased, the combustion instability of the blended fuels decreased significantly, at low load. At n = 2400r/min, pme = 0.53 MPa, compared with diesel, the maximum heat release rate (MHRR) of R70B30 increased by 76.6 %, improving the combustion characteristics of the blended fuel. Moreover, the equivalent specific fuel consumption (ESFC) of RP-3 is 5.56–14.83 % lower than that of diesel, and the effective thermal efficiency (ETE) of RP-3 is 2.8–13.46 % higher than that of diesel under most working conditions.