Dynamic behavior modelling of solenoid valves used for proportional fuel control: experimental validation and parametric study

This comprehensive study develops and experimentally validates the dynamic behavior of solenoid valves under varying inlet pressure and orifice diameter conditions, aiming to provide a database for rocket fuel injection systems. The mechanical and electromagnetic subdomains of the valve are analyzed, and the governing equations for spool motion are derived. These derived equations are implemented into a computational code, producing a numerical algorithm that offers insights into current-time and spool position-time characteristics, enhancing the understanding of valve opening dynamics. Experimental validation of the code is conducted using oscilloscope measurements of the valve in operation. Finally, a parametric study examines the valve's dynamic behavior under varying inlet pressures and orifice diameters, both individually and concurrently. The results show that increasing inlet pressure and orifice diameter causes delays in valve opening time, with the orifice diameter having a significantly greater effect due to its second-order relationship with valve opening time. The obtained data are of great importance as they enable more precise control of rocket velocity and thrust vectoring. The primary objective of this study is to develop a validated nonlinear, coupled electromechanical dynamic model of a direct-acting solenoid valve. Based on this model, the individual and combined effects of operational and geometric parameters such as inlet pressure and orifice diameter on the valve dynamics are quantitatively investigated. The nonlinear influence of these parameters on the valve opening behavior is also analyzed.