曲轴箱通风系统油气分离器的性能研究

Study on Performance of Air/Oil Separator in Crankcase Ventilation System

对1台直列4缸汽油机的曲轴箱通风系统进行了窜气流量和窜气中机油含量的试验研究。应用CFD分析软件Fluent研究了气缸盖罩中迷宫式油气分离器的流动特性,分析最大窜气流量(15 L/min)和最大扭矩(160 N·m)工况点下油气分离过程的速度场、压力场和分离效率。研究结果表明:该油气分离器的多孔过滤板与挡板配合结构在最大窜气流量工况点下能够获得75%以上的分离效果,并且达到50%分离效率时,油滴颗粒的直径小于1.0μm,从而保证对于不同直径范围的油滴颗粒均具有可靠的分离性能。

Blow-by flow and oil content in it were experimentally studied for the crankcase ventilation system of an in-line four cylinder gasoline engine. On this basis, the flow characteristics of labyrinth air/oil separator integrated in the cylinder head cover were studied by using CFD software Fluent. The study focused on velocity field, pressure field and separation efficiency in the separation process under the operating conditions of the largest blow-by flow （15 L/min） and the max. torque （160N,m）. The result shows that by means of the combined structure of porous plate and baffle plates, separation efficiency of the oil/air separator can reach more than 75 % under the operating condition of the largest blow-by flow. When separation efficiency reaches 50%, particle diameter separated is less than 1.0μm, ensuring its reliable separation capability for oil particles of variable diameters.