Combustion Simulation And Analysis Of The Butanol-diesel Mixture Fuel

Because power performance and fuel economy of it are better， more and morepeople pay attention to diesel. Butanol, as a representative of the second generation ofclean fuels, can significantly reduce NOx and soot emissions when used. N-Butanol,as the representative of the second generation substitute fuel, is considered to be zerocarbon smoke emission, and can effectively reduce NOx and PM emissions ofpollutant. In this paper, butanol-diesel hybrid fuel combustion in a diesel enginesimulation study. The numerical simulation, experimental research, theoretical analysisand scientific computing work together, thus it can reduce the time and save cost.Diesel engine combustion and spray numerical simulation has become a kind ofeffective means for researching and designing diesel engine.In this paper, AVL FIRE software was used to conduct and mesh a model of thediesel engine combustion chamber. Combustion and emissions in-cylinder aresimulated from inlet valve close to the exhaust valve opened. The experiments andsimulations were did respectively using pure diesel and5%(volume of butanol)butanol/diesel，and the results are used to calibrate and verify the combustionchamber model. The errors are both within5%， so the calculation model arereasonable and correct, which can be used for combustion simulation of fuel mixture.Using this model，this paper selects four kind of butanol and diesel mixture fuelsuch as B10,B20,B30and B50to research, and analyze the combustion and emissioncharacters. When they reaches the same work conditions, the greater the proportion ofbutanol, equivalent to fuel consumption are increased, and the maximum cylinderpressure and temperature are both increased. But the accumulated release heat arebasically unchanged. With the oxygen content increasing, emissions of soot graduallyreduced, and emission of NOx reduced before increased, B30’s is the highest.This paper also examined the effect of injection timing on combustion of blendfuel. The results show that in-cylinder temperature and pressure will increase with fuel advance of injection angle increases, and the value are essentially the same. Mass ofNOx generated increased, but soot generated total almost unchanged. When advanceof fuel injection angle decrease, in-cylinder temperature and pressure also decrease,and accumulated released heat reduced slightly. The formation of NOx significantlyreduced, but soot volume has slightly increased. Under the same injection time, withthe increase of butyl alcohol in the mixed fuel, average pressure and temperature incylinder is on the rise, and the accumulated heat release basically remain unchanged.NOx of total formation increased after firstly decreased, and soot generated totalamount shows a trend of decrease.