柴油机NO_x排放对进气湿度的敏感性问题研究

Research on the Sensitivity of NO_x Emission for Diesel Engines to Intake Air Humidity

为了研究稳定工况下柴油机的NO_x排放量与进气状态的关系,利用Minitab软件对欧洲稳态测试循环(European steady state cycle,ESC)中A、B、C转速的3个外特性点在不同湿度下NO_x的排放结果进行回归分析和线性拟合,定量分析柴油机NO_x排放对进气湿度的敏感性,探究在试验中通过合理地控制进气湿度以获得具有代表性的NO_x排放结果。NO_x最终排放结果虽然经过温湿度校正因子K_(H.D)的修正,但试验结果表明校正因子的修正作用有限。结果表明,NO_x排放和进气湿度两者之间呈现显著的负相关线性特性。

The regression analysis and linear fitting of emission results from 3 full-load characteristic locations at different speed in ESC circulation is proceeded using Minitab software in order to study the relationship between the NOx emission and the intake air state of the diesel engine under the steady condition. The sensitivity of NOx emission to intake air humidity is quantitatively analyzed so as to obtain representative results via reasonable control of the latter. Although the final NOx emission result has been corrected by the humiture correction factor K H.D , the experimental results show that the correction factor has a limited effect, and a significant negative correlation between NOx emission and intake air humidity is found.