Unsteady Flow Simulation of Directional Control Valve in Electro-Hydraulic Systems by Numerical Analysis

Abstract

The objective of the present paper is a numerical analysis of the transient flow through a 4/3 hydraulic closed center direction control valve. The real-time discharge coefficients corresponding to supply flow difference have been considered. In order to develop an intelligent control system for an electro-hydraulic system (EHS), a new controller has recently been proposed to control those parameters in a complex system. However, a mathematical model of the EHS including the transient parameters has not been clarified. The main objective of this paper is to numerically analyze the dynamic characteristics of the directional control valve and also the flow behaviors in the electro-hydraulic system control. Both the steady state and transient flow though the valve which affect to flow-pressure coefficient were numerically considered. Moreover, this paper presents numerical results, which explain the flow behaviors related with the real-time pressure drop and discharge coefficient. Both a high inlet flow and a large opening spool have determined the pressure drop increment.