关键词: 动力机械工程, 柴油机, 瞬态工况, 燃料十六烷值, 燃烧, 排放

Abstract: With a selfmade transient operation condition control and measure system, the effects of the fuel cetane number on emissions behavior from a small direct injection diesel engine have been studied under steady and transient operation conditions. The experiment results showed that the smoke increases and HC and NOx emission decreases while ignition delay shortens with the increase of the cetane number under steady operation conditions. The smoke increases and NOx emission decreases with the cetane number increases under constant speed and increasing torque conditions. So, an appropriate cetane number should be considered for NOx emissions and smoke opacity reductions. Moreover, there are two limits of the fuel cetane number for the smoke opacity. The effect builds up while the cetane number is less than 50 or more than 60.

Key words: power machinery and engineering, diesel engine, transient operation condition, fuel cetane number, combustion, exhaust emission