高压燃油系统电磁控制阀区域流动特性试验

研究了高压燃油系统单体泵电磁阀区域的流动特性.在电控单体泵泵体上设计了光学透视窗口,利用高速摄像仪器测量控制阀出口端的瞬态流动.对拍摄的图片进行灰度处理,获得了控制阀区域随时间变化的亮度曲线.分析试验结果得出:电控单体泵在控制阀区域出现空泡,形成两相流.由于高速燃油在狭小的控制阀区域流动,以及控制阀多次碰壁,挤压燃油导致空泡的产生.

Flow Characteristic Experiment of Solenoid Valve Region for High-pressure Fuel System

The flow characteristics of solenoid valve region of electronic unit pump (EUP). EUP was rebuilt by using optical visualization observation. A diaphanous glass window was designed in the pump, and the transient flow in the solenoid valve outlet was observed by a high-speed camera. By gray processing of pictures, the brightness curve within the control valve region was acquired. Results showed that cavitation occurred in control valve of EUP and formed the two phase flow phenomenon. The formation of cavitation had two factors, one was due to flow region in control valve where high-speed fuel flow within was quiet narrow, another reason was that the control valve hit the baffle which caused vibration and impingement, hence the fuel was extruded.