For the problem of insufficient movement intensity of working substance at low engine speed and low load ,the new intake strategy based on electromagnetic valve train was put forward to improve engine fuel economy .The strategy allowed the most charge air into cylinder at the early stage of intake to prevent the pumping loss and used the small lift to improve the movement intensity of gas .Compared with other strategies ,the new strategy could lead to a better balance between pumping loss and movement intensity so that engine fuel economy and emissions could improve at low and medium engine speed and load .%基于全柔性化的电磁驱动配气技术,针对发动机低转速小负荷工况工质运动强度不足的问题,提出了一种新的进气策略以有效改善发动机的经济性.其机理是调节气门开启规律使进气初期完成绝大部分充气量,抑制泵气损失的过度增加,进气后期采用较低的升程以保证缸内较高的工质运动强度.通过与其他策略的对比分析可知,新策略在泵气损失和工质运动强度的变化上达到一个良好的平衡,更有利于改善发动机中低转速中小负荷工况的燃油经济性.
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