Abstract

The liquid motion within a partly-filled tank has been associated with reduced overturning limits and braking performance of highway tank trucks. The magnitude of maneuver-induced fluid slosh in a partly-filled tank is strongly dependent upon baffles geometry and baffles layout, apart from many other factors. The conventional lateral baffles can effectively suppress longitudinal fluid slosh induced by a braking or acceleration maneuvers, while their effect on lateral slosh in the roll plane is negligible. Both the overturning limits and braking properties of a partly-filled tank truck could be enhanced through alternate baffles geometry and layout. This dissertation research focuses on the analysis of fluid slosh behavior in a partly-filled tank coupled with different designs of anti slosh baffles. A three-dimensional computational fluid dynamics slosh model is developed for the partly-filled cleanbore, and different designs and layouts of baffled tanks on the basis of the Navier-Stokes equations incorporating the VOF technique. The slosh models are formulated to investigate steady-state as well as transient forces and moments imposed on the container under longitudinal, lateral and combined longitudinal and lateral acceleration fields. A quasi-static model of the partly-filled cleanbore tank is also formulated to examine validity of the dynamic fluid slosh model in terms of steady-state responses. The fluid slosh characteristics are analyzed under different fill volumes corresponding to varying cargo load and subjected to external excitations representing steady-turning, straight-line braking and braking-in-turn maneuvers. The fluid slosh analyses are also carried out to explore the anti-slosh effectiveness of baffles and to evaluate the effects of baffles design factors, such as baffle curvature, orifice size and shape of the orifice. Alternate design concepts and orientations of baffles are also explored with goals of limiting both the longitudinal and lateral slosh. Concepts in obliquely placed baffle, partial baffles, and partial baffles arranged in an alternating pattern are proposed and analyzed for their effectiveness in limiting the fluid slosh. The results of the study suggest that obliquely placed baffles could help to limit lateral as well as longitudinal fluid slosh under lateral as well as combined lateral and longitudinal acceleration excitations.