Dynamic Investigation on Effective Bulk Modulus of Hydraulic oil Using Piezoelectric Transducers

Abstract

The effective bulk modulus of hydraulic oil can greatly affect the dynamic characteristics and performance of hydraulic power system, in this study, a new method based on piezoelectric transducers for investigating the fluid effective bulk modulus dynamically is proposed. In dynamic measurement, the hydraulic oil is alternately compressed by the piezoelectric actuator and the piezoelectric ceramic sheet served as a sensor in the chamber can detect the pressure variation and output the alternating voltage, which can reflect the characteristics of effective bulk modulus of hydraulic oil. Then the effects of working pressure up to 10 MPa and whether to exhaust the air on the effective bulk modulus of hydraulic oil are experimentally studied. The experimental results show that the effective bulk modulus of hydraulic oil can be improved by increasing the working pressure and exhausting the air before pressurization.