Realization of low-frequency omnidirectional curve beam resonator (OCBR): Analytical spectral formulation and experimental characterization

The primary contribution of this study lies in the strong alignment between analytical, numerical, and experimental results, underscoring the validity and practical applicability of the Omnidirectional Curved Beam Resonator (OCBR) design in diverse structural configurations. This research encompasses the realization, characterization, and development of a spectral element formulation for the OCBR, a novel device engineered for vibration control within hollow structures. The spectral element matrix for the curved beam elements is formulated considering all six degrees of freedom using rigid body dynamics and mass inertia, enabling accurate dynamic analysis. Analytical solutions for the Frequency Response Function (FRF), derived using the spectral matrix and fixed boundary conditions, exhibited a close match with experimental results, validating the accuracy of the proposed model. Experimental setups with different orientations consistently observed resonant frequencies at 26 Hz, 32 Hz, 72 Hz, and 78 Hz, corresponding to the OCBR's axial, in-plane, and out-of-plane vibrations, further affirming the theoretical predictions. Additionally, numerical simulations performed in COMSOL provided detailed insights into the system's behavior, with deflected shapes at resonant frequencies corroborating the analytically predicted resonances. This study demonstrates the OCBR's potential as a highly effective solution for vibration control, particularly in attenuating vibrations in the lower frequency range, representing a significant advancement in structural vibration mitigation techniques.