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Baffles are known to help reduce the amplitude of fluid slosh in partly filled tanks, particularly during braking and acceleration. The transient fluid slosh approach is proposed to evaluate the effectiveness of baffles designs. A computational fluid dynamic (CFD) fluid slosh model is developed using the VOF (volume of fluid) technique coupled with a Navier-Stokes solver. The validity of the model is demonstrated using the experimental data acquired with a scale model tank. The validated CFD model is subsequently formulated for a full scale tank and simulations are performed under excitations idealizing the straight-line braking maneuvers to investigate the anti-slosh role of four different transverse baffles concepts. The fluid slosh responses are analyzed in terms of the fundamental slosh frequency, and the resulting forces and moments under different fill volumes of liquid cargos of constant load.

Transient fluid slosh within a partly-filled tank could impose high stresses on the tank structure and affect the directional performance in an adverse manner. A three-dimensional nonlinear model of a partly filled circular cylindrical tank with and without baffles is formulated and analyzed to derive the pressure distribution over the wetted tank surface. The baffles and end caps are modeled with curved shapes in accordance with the current standard. The analyses are performed for 40% and 60% fill volumes and different types of baffles, including single-nozzle and multiple-orifice baffles, using the FLUENT software under time varying acceleration fields representing simultaneous braking and turning maneuvers. The pressure data are further analyzed to evaluate steady-state and transient slosh forces, load shifts along the longitudinal and lateral axes, and the roll, pitch and yaw moments imposed on the tank structure.

The unique difficulties associated with low frequency and large amplitude ride vibrations of off-road tractor are summarized. Concept of a cab suspension system for improving the ride quality of off-road tractors in the bounce, longitudinal, lateral, pitch and roll modes is explored. Influence of suspension parameters on the ride performance is presented followed by selection of optimal suspension parameters. It is shown that a cab suspension would provide improved performance in the longitudinal and pitch modes alone. Ride analysis of the cab suspension with a sprung seat reveals satisfactory bounce ride. Roll and lateral ride of the off-road tractor can be improved significantly through alterations in the cab geometry. The ride performance of the optimal suspensions is assessed with reference to ISO (International Standards Organization) specified “fatigue decreased proficiency” (FDP) boundaries.