几种消除汽车燃油蒸发回收系统气流脉动及振动噪声的方案研究

Study on Eliminating the Vibration,Noise and Gas Pulsation Induced by Fuel Evaporation Recovery Systems of Automobiles

为了消除国六车燃油蒸发回收系统中气流脉动及其引起的振动噪声,在电磁阀线圈两端反向并联整流二极管,可提高电磁能利用率,降低阀门振动及气流脉动和脉动引起的车内噪声,从而提高气体流量性能。缩小电磁阀进气管口截面积,在电磁阀上游管路串联扩张腔以及扩张腔内增加带孔隔板等方法措施,可使气体在突然变化的截面产生碰撞和漩涡,借助能量损失使气流脉动峰值降低。而在电磁阀体进气侧加装膜片弹簧,也能够有效消除管道内气流脉动能量及其引起的车内噪声。通过设计合适的结构特征参数,这些方法措施都能有效消除气流脉动及其引起的振动噪声。综合对比试验结果表明,在电磁阀线圈反向并联整流二极管同时缩小电磁阀进气管内径截面面积的方案是效果最好、成本最低的,能有效消除车内噪声,明显提高高占空比下的气体流量,是一种较优的方案。

Some optimal schemes are proposed to eliminate the fluctuation,vibration and noise of the gas flow in the fuel evaporating systems of automobiles.In these schemes,both ends of the coil of the electromagnetic valve are reversely connected to a rectifier diode by parallel connection,which can raise the utilization efficient of electromagnetic energy and reduce the noise and vibration of the valve,the gas pulsation produced by the valve vibration and the internal noise induced by the gas pulsation,so that the performance of the gas flow is improved.In addition,reducing the cross section of the inlet pipe of the solenoid valve or inserting an expansion cavity with perforated diaphragm between the solenoid valve and active carbon canister can make the gas pulsation energy loss by colliding and swirling in the position where the cross section of the cavity suddenly changes,so that the peak value of the gas pulsation can be reduced.Moreover,adding a diaphragm spring between the cover and the valve in the solenoid valve body can also effectively eliminate the gas pulsation energy in the pipe and the corresponding internal noise.By designing the appropriate structural characteristic parameters,these measures can effectively eliminate the gas pulsation and the vibration and noise caused by the flow.The comprehensive comparison of the test results of these measures shows that among these measures,connecting both ends of the coil of the electromagnetic valve to the rectifier diode reversely with parallel connection and meanwhile reducing the cross section of the inlet pipe of the valve have the best effect and lowest cost.It can significantly improve the gas flow rate and effectively eliminate the noise inside the car.