Fluid-structure interaction induced vibration of a lubrication device for space applications

A positive-feed lubrication method was proposed to overcome the deficiencies of passive-feed lubrication method for space applications. To achieve the purpose of positive lubrication, a piezoelectric micro-droplet generator with simple structure and production convenience was developed. Natural frequency and vibration mode shape are both important for the droplet formation and ejection. An equivalent model considering the piezoelectric structure-liquid interaction and the effect of transmission of the pressure wave was presented and finite element analysis was used to obtain the natural frequency and vibration mode shape. Laser doppler vibrometer was then used to measure and check the actual vibration mode shape and natural frequency. Validity of the structure-liquid finite element model and practicability of the method were both proved by comparing the results.