Passive suppression of vortex-induced vibrations using a nonlinear energy sink—Numerical and analytical perspective

This study investigates the suppression mechanism of instabilities induced by fluid–structure interactions (FSI) using passive vibration absorption devices, such as nonlinear energy sink (NES). The present FSI framework comprises a low-order phenomenological model, wherein wake effect is modeled classical Van der Pol oscillator. structure represented cylindrical bluff body with degree-of-freedom along cross-flow direction. response NES-augmented exhibits specific relaxation type oscillations, referred to strongly modulated (SMR), passively suppressing high amplitude vortex-induced vibrations (VIV). underlying SMR studied an analytical approach based on Complexification-Averaging (CXA) technique. Using CXA technique, slow flow for coupled system NES attachment effectively, revealing beating regimes and initiation targeted transfer (TET) mechanism. Subsequently, transient resonance capture, implying significant from NES, results in effective VIV suppression. occurrence SMRs explained analyzing global dynamics invariant manifold (SIM) derived system. resultant SIM topology reveals jump phenomenon between stable branches, jumps lower branch higher through SMR. novelty this lies identifying uses technique explain modeling 3-DOF attachment. Furthermore, optimal operational parameter ranges efficient design are identified parametric slow-flow model.