Research on Stability and Control Strategies for a Spring-Loaded Valve with Bypass Outlet

•In this study, nonlinear dynamical equations are established for spring-loaded valves with bypass outlets.•Under constant inlet flow rate conditions, the valve disc's unstable flow interval is characterized by small flow.•The valve disc displays complex behavior under inlet time-varying flow conditions. A distinct frequency lock-in phenomenon occurs within the flow range of disk instability for fluctuating flows, while oscillations during the opening process are more pronounced compared to those in the closing process.•The introduction of a bypass outlet and an effective feedback control strategy substantially enhances the stability of the valve disc at low flow rates, showcasing the potential for improved valve performance in such conditions.