Vibration Mitigation in Partially Liquid-Filled Vessel using Passive Energy Absorbers

TL;DR

This study investigates passive vibration mitigation techniques for partially liquid-filled tanks under impulsive forces, using numerical models to evaluate the effectiveness of linear and nonlinear energy absorbers in reducing structural vibrations and hydraulic impacts.

Contribution

It introduces a combined modeling approach for liquid sloshing and tank wall impacts, and assesses passive vibration absorbers' performance in a reduced-order model.

Findings

Passive absorbers can significantly reduce tank vibrations.

Nonlinear energy sinks outperform linear dampers in certain scenarios.

Finite element analysis reveals internal resonance conditions.

Abstract

This paper treats possible solutions for vibration mitigation in reduced-order model of partially-filled liquid tank under impulsive forcing. Such excitation may lead to hydraulic impacts applied on the tank inner walls. Finite stiffness of the tank walls is taken into account. We explore both linear (Tuned Mass Damper) and nonlinear (Nonlinear Energy Sink) passive vibration absorbers; mitigation performances are examined numerically. The liquid sloshing mass is modeled by equivalent massspring-dashpot system, which can both perform small-amplitude linear oscillations and impact the vessel walls. We use parameters of the equivalent mass-spring-dashpot system for well-explored case of cylindrical tanks. The hydraulic impacts are modeled by high-power potential and dissipation functions. Critical location in the tank structure is determined and expression of the corresponding local mechanical stress is derived. We use finite-elemet approach to assess the natural frequencies for specific system parameters and to figure out possibilities for internal resonances. Numerical evaluation criteria are suggested to determine the energy absorption performance.