直动型溢流阀的流固耦合建模与动态特性研究

直动型溢流阀被广泛用于水下动力设备的供能调节，但下潜水深的变化时常使得其动态稳定性无法保证，以至于在到达一定水深之后，溢流阀阀口会出现异常的压力波动现象，影响其正常的工作状态。为此，开展流固耦合分析，建立了直动型溢流阀的两自由度动力学模型。通过无因次化后模型的求解，实现了对试验测试信号中振动深度的准确复现，并进一步分析了溢流阀阀芯的轴向和纵向振动状态随水深的变化，以及在部分深度下阀芯振动的多稳态共存现象。所建立的动力学模型中的非线性因素为试验测试信号中发现的压力波动特征提供了理论解释，从而为通过对溢流阀的优化设计来解决溢流阀的大振幅脉冲振动提供了模型支撑。

Fluid-Structure Coupling Modelling and Dynamic Analysis of a Direct-Acting Relief Valve

Direct-acting relief valve is widely applied in the energy supply of underwater power equipment; however, its dynamic stability is generally challenged by the change of the water depth, namely the hydraulic pressure condition. Sudden pressure jumps are observed at valve port in certain depths, which brings harmful influences on its normal working condition. A two degree-of-freedom dynamic model for a direct-acting relief valve is developed based on fluid-structure coupling analysis, and then its corresponding nondimensional mathematical model is solved numerically. The results of numerical simulations are in agreements with the experimental measurements for the water depths of impulse vibrations of the relief valve. Moreover, the variations of both the axial and longitudinal vibrations of the valve element as the water depth, and the coexistence of its multi-stability conditions in certain depths are analysed. The nonlinear characteristics of the developed model provide a theoretical explanation for the pressure fluctuation characteristics explored in the experimental measurements, which further supports the system optimization to avoid large amplitude vibrations of the relief valve.