凸轮轴型线设计对PFI汽油机低速性能影响的试验研究

凸轮轴是发动机进气系统的重要组成部分,不同型线直接影响发动机的性能和排放水平。本文通过对PFI增压汽油机进行不同型线的凸轮轴计算分析和试验验证,研究了凸轮轴型线对发动机性能及燃烧特性的影响。试验表明,适当减小气门重叠角可以有效提高低速扭矩,但是燃烧变差,适当增大进气门升程及包角,可以增加扫气的同时提高燃油雾化效果,改善燃烧降低油耗,但对扭矩无明显影响。

Camshaft is an important part of the engine air intake system, different type line directly affect the engine performance and emissions levels. Based on PFI for different lines turbocharged gasoline engine camshaft calculation analysis and test, studied the camshaft hnes influence on engine performance and combustion characteristics. Test shows that proper reducing valve overlap Angle can effectively im- pro,ee the low -speed torque, but burning, appropriate increase into the valve lift and Angle, can in- crease the scavenging effect of at the same time, improve fuel atomization, improve combustion of fuel, but had no obvious effect on the torque.