Simulation Of Main-post Injection Multi-parameter Strategies Based On Dme/Diesel Blended Fuel Burning

The relationship of engine indexes has been the focus of research. According to4100QBZL engine, models and numerical simulation were obtained by means of software Fire. Firstly, study was carried out about the effect of dimethyl ether mixed burning ratio on the mixed fuel atomization amount of the engine, the combustion law, average temperature and pressure in cylinder, the temperature field and concentration field et al. Tests show that D30mixed fuel is better than D10and D20in aspect of the mixed fuel atomization amount, burning and emission. Dimethyl ether mixed burning has favorable effect on improvement of the engine’s fuel spraying, burning and emission, especially the emission of Soot.Based on the burning of D30dimethyl ether and gasoline mixture, orthogonal experiment should be carried out to match factors of fuel injection advance angle, interval of a main injection and a post one, post injection duration and the amount of post injection optimally. Effects of the four factors on launch power, economy and emission were studied with the Visual Analysis method, without consideration of the interaction of post injection. Results present that, fuel injection advance angle is the main factor that influences engine performance; the engine power and economy is affected by the interval of a main injection and a post injection significantly; the amount of post injection has a greater effect on the emission; but there is faint effect of post injection duration on the four factors.The effects of post injection on engine performance parameters are studied with the variance analysis method. Injection amount is affected both by interval of main post injection and post injection duration. But their influence is not significant. The interaction between interval of main post injection and post injection affect dynamic property and Soot emissions greatly. So when considering the influence of the interactions on the engine performance indicators, we can only take the interval of main injection and post injection into consideration. Factors influencing the engine performance indicators are studied with comprehensive analysis method. And the optimizing combination scheme is A1D1E3. Economy and emissions are improved greatly When compared to the original one.