Research on the rotational inertia of radial piston pump and the optimization method of the pump parameters
This paper aims to propose a method of optimizing the structure of radial piston pump from the aspect of reducing the rotational inertia. A modeling method based on basic dimensions and scale factors is developed. By using this method, three different types of radial piston pumps are studied. And the relative rotational inertia coefficient is adopted to evaluate the difference among them. Further study states that the relative rotational inertia coefficient changes along with the eccentricity ratio and the thickening factor. Finally a criterion is obtained, which could be used to optimize the structure and the dimensions of radial piston pumps.
Direct drive volume control electro-hydraulic servo active mass driver system
Aiming at the disadvantages of traditional AMD drive device,such as large volume,high cost,complex system,more energy consumption,an innovative driver-Direct Driving Volume Control(DDVC) servo system for AMD is proposed based on the volume control of electro-hydraulic servo system.The mechanical models of motor control,hydraulic power mechanism,hydraulic actuator and other sub-structures of DDVC electro-hydraulic servo system were separately established as well as the mathematical model of direct drive volume control electro-hydraulic servo actuator.Taking an actual project's experimental prototype as a standard,the parameter optimization and the match computation were carried out,and the DAMD control system are designed and processed.The dynamic characteristics of the power mechanism controlled by pump are not high because the DAMD system dynamic characteristics are low.DAMD control system can be used to substitute the traditional AMD control system for high-rise structure or large-span structure to realize active control of structural vibration.
An experimental study on the control of pressure transients using an orifice
Control of pressure transients in a hydraulic system may be important and necessary to avoid failure and to improve the efficiency of operation. This study addresses the design and use of an orifice to provide the desired control to a hydraulic actuator system. Control is accomplished by installing orifices at appropriate locations in the system. Experimental results show that an orifice can be used to obtain control of shock and the control level depends on the orifice size, orifice type, operating pressure and flow rate. From the experimental data, an empirical design chart for controlling pressure rise using an orifice has been derived.