Experimental investigation on the sloshing dynamics of first- and super-harmonic resonances in a rectangular tank with and without a vertical baffle

Abstract

The sloshing dynamics of the first- and super-harmonic resonances in clean and baffled tanks were experimentally investigated within a wide excitation frequency range. The first-harmonic resonance (i.e., primary resonance) was generated on the liquid surface when the excitation frequency approached the natural frequency in the sloshing system. The installation of the vertical baffle effectively suppressed the violent sloshing at the excitation frequency near the lowest natural frequency. However, the vertical baffle negligibly suppressed the sloshing at higher frequencies. Additionally, the vertical baffle installation locations influenced the natural frequency of the system. In addition to the first-harmonic resonance, the super-harmonic resonance (i.e., secondary resonance) was excited, even when the excitation frequency was far from the natural frequency of the system. Furthermore, the effect of liquid viscosity on the sloshing dynamics of first- and super-harmonic resonances is investigated. It demonstrates that the liquid viscosity has a significant suppression effect on the resonant sloshing at the lowest and the higher modes. Due to the reduction of the nonlinearity, the super-harmonic resonance become difficult to be excited.