Optimization of nonlinear energy sinks for broadband vibration suppression in marine propulsion systems

This study presents an optimization methodology for nonlinear energy sinks (NES) aimed at attenuating longitudinal vibration in marine propulsion systems. A cubic-stiffness NES model integrated with propulsion dynamics was validated through the harmonic balance and Runge-Kutta methods. An enhanced Harris Hawks Optimization (HHO) algorithm simultaneously minimizes force transmission and maximizes energy dissipation. The optimized NES effectively reduces vibrations across multiple resonances. Sensitivity analysis identifies the mass ratio as the dominant parameter, while nonlinear stiffness plays a key role in balancing the two objectives. These findings establish practical design guidelines for NES in marine propulsion, demonstrating that effective vibration suppression can be achieved with minimal added mass.