Study On The Test Of Methanol/Diesel Compoud Combustion And Its Combustion Characteristics

With the reduction of petroleum resources and the increasingly stringentemission regulation, high efficient alternative fuels have become an importantresearch direction of internal combustion engine. Methanol presents a promisingprospect as an alternative fuel. This thesis encircles the realization of applying theDMCC mode into vehicle and the further study on combustion character ofdiesel/methanol dual fuel is conducted according to the road test results.First of all, a Beijing flag van is mechanically transformed, which is includednozzles installed on the intake pipe of the engine for methanol injection and amethanol input pipeline installed in the car. In the circuit system design part, thispaper developed the electric control system and fuel injection system, which is laid afoundation for methanol/diesel combustion mode in the diesel vehicle.This paper researches and analysis the fuel combustion characteristic of the testvan transformed, which includes temperature characteristic (maximum combustiontemperature, inlet temperature, exhaust temperature), pressure characteristics,replacement rate and replacement ratio and thermal efficiency of the engine. And thispaper also measures the exhaust emission of the test van, analysis and forecasts thedata. The experimental results show that: Compared with the baseline engine, theform of heat release rate is changed significantly by the injected methanol,simultaneously the ignition point is delayed a lot. The heat release rate is significantlyaccelerated, the maximum heat release rate increases and the original heat release raterises sharply. Besides, the proportion of premixed combustion increased, and theproportion of diffusion combustion decreases. This burning method could be veryeffectively to reduce emissions of the engine and improve and enhance the emissionquality of diesel engine in China.