直喷式柴油机的NO排放预测与实测对比分析

Prediction of NO Emission and Experimental Comparative Analysis for Direct Injection Diesel Engines

通过对直喷式柴油机工作过程的模拟,把燃烧过程以曲轴转角划分时间段,每段内先进行11产物7反应法的等压绝热燃烧平衡计算,得到产物的平衡浓度,然后利用扩展了的ZeldovichNO生成机制,按照化学反应速率进行修正,逐步叠加至燃烧结束,得到NO的排放浓度 将预测的结果与CZ480QA直喷式柴油机十三工况的排放数据进行对比分析。

The single Vibe function approximates the actual heat release characteristic of DIdiesel engine through operating process simulation specifying points versus crank angle. In each combustion period, it is assumed that the fuelair mixture gas is combusted in constant pressure and adiabatic condition. Mole fractions of 11 product species can be obtained by chemical equilibrium calculation and the concentration of the product NO is modified by using extended Zeldovich NO mechanism. The whole mole of NO is accumulated until the end of combustion. In the end the results are compared with the experimental data of CZ480QA DIdiesel engine and further improvements are proposed.