Abstract
In order to decrease the smoke emission of coconut oil methyl ester (CME) with 1-butanol, increasing the 1-butanol mixing ratio was tried, and the fuel properties, combustion characteristics and exhaust emissions of the CME/l-butanol blends were investigated using a DI diesel engine. With increase in 1-butanol content (10-40 mass%), the smoke emissions decrease, the ignition delay becomes longer and the HC and CO emissions increase especially at low load conditions. By adding the cetane number improver to CME/l-butanol blend, the ignitability is improved and the 1-butanol mixing ratio can be increased up to 60 mass%. However, the smoke emissions slightly decrease because the premixed combustion ratio decreases due to the shorter ignition delay.
