An advanced flexible dynamic model and experimental verification for armature assembly in servo valve

• Demonstrate higher accuracy in predicting low and high frequency responses. • Experiment shows exhibit universal applicability to real armature assemblies. • Addresses the limitations of conventional models in predicting non-flow-induced high frequency self-excited vibrations. The armature assembly is the core component of servo valves, making its dynamic characteristics critical to both operational performance and stability studies - particularly requiring broadband multi-modal dynamic analysis for stability investigations. To efficiently and accurately determine the characteristics of the servo valve, a multi-beam coupled model (MBCM) of the armature assembly has been developed. The finite element method (FEM) and experiments were employed to validate the accuracy of the multi-beam coupled model. Experimental results show that the proposed model is not only valid for simplified armature assemblies, but also remains applicable to real ones. While maintaining excellent first-modal accuracy, minor reductions in precision were observed in high-frequency predictions, attributable to discrepancies between the higher-order modal shape deformations of the armature and the fundamental assumptions of the MBCM. In the analysis of self-excited vibrations in servo valves, the servo valve model based on MBCM accurately predicts vibration patterns consistent with experimental observations- a capability not achievable by existing models, demonstrating the distinct advantages of the MBCM over current methodologies.