Study on the Vibration Characteristics of the Spraying Needle Excited by Electro-hydraulic Source Based on Luminous Energy Method

When one kind of liquid was atomized by a metal needle in the electric field, violent vibration of the spraying needle could be observed clearly, and the atomizing stability was affected by it seriously. To explore the cause of the needle’s vibration and weaken its negative effect, an optical energy method was adopted and some characteristics of the vibration were investigated. The principle of the optical energy method was very simple, it was just a transformation from mechanical information of the needle’s vibration to an optical signal composed with luminous energy features and received by a photodiode. The prototype of it was composed by a luminous source system and a testing circuit cored with MCU STC89C52. After the electronic signal transferred from the luminous energy was analysed, some characteristics come from different needles under different working conditions can be obtained. Some results are: the cause of the vibration comes from dual incentives of the electrostatic field and the atomized liquid jet, in view of mechanical structure, the length and diameter of the spraying needle was the main factors affecting the vibration amplitude and frequency, considering the flow rate flow through the spraying needle, there are different starting vibration voltages for different flow rate at the same length and diameter.