Experimental study on the application of n-butanol and n-butanol/kerosene blends as fuel for spark ignition aviation piston engine

Spark ignition aviation piston engine which mainly equipped in light aircrafts is the important part of aviation power. Due to the particularity of operation conditions, spark ignition aviation piston engine still relies heavily on gasoline. The application of renewable alternative fuel is an effective way to reduce the carbon emissions of air transport industry. Meanwhile, the application of high flash point fuel is expected to improve the safety of aircraft. In this paper, n-butanol was proposed as fuel for spark ignition aviation piston engine to replace gasoline. The engine performance fueled with n-butanol were studied and compared to gasoline. N-butanol had shorter flame development duration and rapid combustion duration than gasoline. The heat release of n-butanol was more concentrated and n-butanol could achieve higher brake thermal efficiency. The CO and NOx emissions of n-butanol had significant advantages over gasoline. However, the application of n-butanol led to an obviously increase in fuel consumption. Then, n-butanol/kerosene mixed fuel with higher energy density were proposed to be the fuel of spark ignition aviation piston engine. Due to the combustion detonation, the knock limited spark timing of n-butanol/kerosene was quite delayed which resulted in the low engine efficiency. Improving the antiknock performance of n-butanol/kerosene based on high octane additives was the key to improve their performance in spark ignition aviation piston engine.