CFD simulation of flow-pressure characteristics of a pressure control valve for automotive fuel supply system

Abstract

This study aims to elaborate on specific computational fluid dynamics (CFD) simulation methods for fitting the flow-pressure curve of a pressure control valve, which is spring-load valve widely used in the automotive fuel supply system. Given that the couple mechanism exists between the flow field in the valve and the spring system, numerous researchers chose to fit the characteristic curve with experimental approaches but scarcely focused on CFD methods. A direct CFD method is introduced in this study to solve this problem. Two evaluation criteria are used to determine whether the internal flow is physically real. An experiment is conducted to verify the simulation results, and the accuracy of this CFD method is proved. However, it is designed to solve one operating condition with fixed spring parameters and the accuracy depends on the amount of operating conditions. Thus, an indirect CFD method is developed based on the well-elaborated valve-governing equations to improve the efficiency and broaden the application extension. This method aims to simulate the exact value of the equation constants to uncouple the flow by numerical method. It is capable of dealing with changed operating conditions and varied spring parameters, and the results are also verified. The visualization of the internal flow provides a better understanding of the flow fields in the valve. The valve gap directly influences the hydraulic force distribution on the spool and causes most pressure loss. The physical meaning of the function constants are explained based on the flow analysis.