Abstract
The aim of this paper is to compare the performance of a hydraulic vane actuator with oil and water as the pressure medium. If the same performance level can be achieved with water and oil hydraulics, water as the pressure medium is preferred in applications where external oil leakage is not allowed or in applications that need fireproof fluids.
In order to compare the performance, a theoretical analysis of the actuator characteristics is carried out. The analysis includes a linear model of the hydraulic drive and allows identifying which factors should be analyzed in detail. As a result of this study, the parameters that greatly affect the performance of a hydraulic drive are identified (mainly, natural frequency, leakage, friction, damping and servovalve behaviour).
To experimentally verify the influence of these factors on the behaviour of the vane actuator, a set of measurements is designed to be able to identify the critical parameters.
During this study, special attention is paid to friction and leakage effects. Due to the lower water viscosity, sealing of the fluid chambers is difficult and internal leakage is difficult to avoid.
