A novel low pressure-difference fluctuation electro-hydraulic large flowrate control valve for fuel flowrate control of aeroengine afterburner system

To address the control accuracy of large fuel flowrate during pressure fluctuation, a novel electro-hydraulic fuel metering unit(FMU) is constructed for afterburner fuel system of military aeroengine. Different from the previous FMU, the proposed FMU can achieve the higher precision opening control by a new metering valve with double control chambers(MVDCC), and realize the lower pressure difference fluctuation regulating by a novel two-stage constant pressure difference compensated valve(CPDCV) with dynamic damping orifice and damping piston. The experimental and AMESim simulation results verify the validity and superiority of the novel FMU. Since the temperature-induced variation in fuel properties and device capabilities may degrade or even impair the properties of novel FMU, the discharge flowrate is analyzed by global sensitivity analysis to research the effect proportion of each factor, the temperature effect is explored to ensure the working reliability in long-span temperature variation. Finally, the optimization of structure parameters for novel CPDCV can further reduce pressure difference fluctuation during pressure regulation, and the overshoot, adjust time and the integral of time multiplied by absolute value of error(ITAE) can be reduced by 24%, 30% and 26%, respectively. This paper provides a reference for improving the stability of large flowrate during pressure fluctuation.