Numerical and experimental investigation on the flow-rate stabilization features of a novel flow control valve design for variable-thrust spacecraft engine

Abstract Precise modulation of propellant flow is crucial for thrust control in variable-thrust liquid rocket propulsion systems. This study presents investigations on a novel passive Pressure-Compensated Flow Control Valve (PCFCV) featuring a self-adjusting orifice mechanism. The mechanism adjusts the effective flow area in response to changes in inlet and outlet pressures, enabling stable flow regulation without active feedback. A lumped-parameter hydraulic resistance network was developed in MATLAB to simulate steady-state flow behavior. Transient dynamics and nonlinear pressure–flow interactions were modeled using a Simulink-based framework. The performance of the proposed PCFCV was experimentally demonstrated using a high-precision flow test facility with water as the working fluid. The results show that the valve achieves flow-regulation accuracy within ± 3% across a wide range of differential pressures, demonstrating its capability for stable flow regulation under the tested conditions. The numerical predictions and experimental observations show close agreement and highlight the effectiveness of the passive compensation mechanism. The proposed PCFCV offers a viable alternative to conventional actively controlled throttle valves by significantly reducing system complexity while maintaining high flow-regulation accuracy, making it a promising candidate for next-generation throttleable liquid-rocket engine applications.