This article reports on an experimental study conducted to investigate slosh forces and moments caused by fluid slosh within a partly-filled tank subjected to lateral and longitudinal excitations applied independently. The experiments were performed on a scale model cleanbore and a baffled tank with laterally placed single- and multiple-orifice baffles. The experiments were conducted for three different fill volumes and different types of excitations: continuous harmonic and single-cycle sinusoidal excitations of different amplitudes and discrete frequencies. The dynamic forces and moments caused by fluid slosh with the baffled and cleanbore tank configurations were measured for different fill volumes and excitations using three-axis dynamometers. It is shown that the resulting forces and moments comprise many spectral components that can be associated with the excitation, resonance, and vibration and beat frequencies. Modulation of excitation frequency with the resonant frequency was also evident for all fill conditions and tank configurations when the two were in close proximity. The results also showed that the peak amplifications of forces and moments occur in the vicinity of the resonant frequency. At higher frequencies, the peak magnitudes of the forces, however, reduced significantly to values lower than the inertial forces developed by an equivalent rigid mass. At a given excitation condition, the slosh force amplitude increased with a decrease in the fill volume. It was also observed that the presence of baffles has negligible effect on the lateral slosh force and the corresponding resonant frequency. However, it caused a significant increase in the longitudinal mode resonant frequency. The baffles greatly reduced the amplifications in longitudinal force and pitch moment under longitudinal acceleration excitations.

The straight-line braking performance characteristics of a partly filled tank truck with and without transverse baffles are investigated in the presence of transient fluid slosh within the tank. The dynamic interactions of the floating cargo with the vehicle are evaluated by integrating a dynamic fluid slosh model of the partly filled tank with and without transverse baffles with the seven-degrees-of-freedom pitch plane model of a tridem truck. The dynamic fluid slosh within the tank containing equally spaced four curved single-orifice baffles with flow equalizer is modelled using three-dimensional Navier—Stokes equations coupled with the volume-of-fluid equation and analysed using the FLUENT software. The coupled tank—vehicle model is subsequently analysed to determine the straight-line braking properties for different fill volumes, magnitudes of braking treadle pressure, and road surface adhesion coefficients, while the cargo load is considered to be constant. The results show interactions of the sloshing cargo with the vehicle. A degradation of the braking performance of the partly filled tank truck is evident in the presence of transient fluid slosh, particularly in the absence of baffles. The braking performance, however, is highly dependent upon the fill volume, presence of baffles, and severity of braking input. For a clean-bore tank truck, the stopping distance increases monotonically with decreasing fill volume, while the addition of transverse baffles in general results in considerably shorter stopping distance. The baffled tank truck, however, reveals a relatively shorter stopping distance under an intermediate fill condition (approximately 52.1 per cent), compared with the lower and higher fill volumes. Although the analyses are limited to conventional single-orifice baffles, the proposed coupled vehicle—tank model could serve as an important tool for exploring alternative baffle designs and layouts.

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