Vibration Damping Through Liquid Sloshing, Part 2: Experimental Results

Experiments designed to evaluate performance of partially filled torus shaped nutation dampers, undergoing steady-state forced excitation in translational motion, are described. The forces exerted by the fluid on the damper walls are measured over a range of system parameters. Results suggest that low liquid heights and large diameter ratios with the system operating at liquid sloching resonance lead to increased damping. On the other hand, low Reynolds numbers and presence of obstacles, such as baffles, tend to reduce the peak efficiency by restricting the action of the free surface. The theory, based on the potential flow approach and corrected for viscosity near the solid boundary, generally yields the right trends while underestimating the amount of dissipation within the torus. A flow visualization study qualitatively confirms the nature of the mode shapes predicted by the theory.