The Influence of Methanol Mass Ratio and Compression Ratio on Combustion Characteristics of Dual-Fuel Engine

A study was conducted in a dual-fuel engine to explore the influence of methanol mass ratio and compression ratio on the combustion characteristics, and a set of methanol injection device was installed on a single cylinder diesel engine. The results show that, with the increase of the methanol mass ratio, the in-cylinder pressure gradually decreases, the pressure rise rate and the heat release rate increase firstly and then decrease, the start of combustion gradually postpone and combustion duration gradually short. The decrease of the compression ratio causes the increase of the peak heat release rate, but it has complex effects on the peak in-cylinder pressure, the peak pressure rise rate, start of combustion and combustion duration. When the compression ratio is 15.9, the peak in-cylinder pressure and the peak pressure rise rate are highest, the start of combustion is earliest and the combustion duration is longest.