Effects of liquid sloshing on the strength and fatigue life of the subframe of a B-Train liquid cargo vehicle

The work in this thesis presents a novel approach for estimating the static/dynamic strength and fatigue life of a subframe of a B-Train liquid cargo tank vehicle under the effect of forces generated during the dynamic movement of liquid inside the tank. The present research in this thesis describes the necessity of consideration of the liquid sloshing effects in a liquid cargo tank vehicle. The tank vehicles transporting liquid cargo are the most unstable vehicles operating on the roads, yet very few researchers have tried to relate fatigue failure and liquid sloshing. Fatigue analysis of heavy liquid cargo vehicles is insignificant without considering the effects of the liquid motion taking place inside the tank container. The present research presents an effective study of the traditional static analysis and the dynamic approach. It also describes the importance of dynamic/transient analysis in estimating the life of a vehicle structure. This thesis provides a novel methodology to estimate the fatigue life of the B-Train liquid vehicle by quantifying the dynamic forces generated inside the tank. The work is then extended by presenting a methodology to integrate these forces due to the fluid dynamics with the structural dynamics of the subframe. A transient analysis with the load acquired is also performed to generate the stress/strain history. The stress spectra are implemented in an existing fatigue analysis technique to estimate the service life of the subframe. The result of the research provides guidance for a tank vehicle designer to develop a B-Train subframe.