Analysis of sloshing-induced loads on the fuel tank structure

Abstract

Fuel sloshing is a source of major concern in the structural design of fuel tanks in heavy duty trucks. It is caused due to the free surface motion of fuel in partially filled containers induced by external agitation. With capacities as high as 900 litres, this phenomenon is capable of causing fuel to impact the container tank with high forces, exposing the vulnerable parts of the tank to heavy dynamic loads. This highly nonlinear phenomenon is simulated using the commercial computational fluid dynamics (CFD) code STAR-CCM+. The two phase (air-fuel) problem is solved using the volume of fluid (VOF) interface capturing approach. Owing to the thin walled structures of the fuel tank, it becomes indispensable to cater to the effects of fluidstructure interaction (FSI). This need is amplified with the ever-increasing design constraints and use of novel materials for fuel tanks aiming at weight reduction. To this end, a partitioned FSI methodology is employed by coupling the CFD and Finite Element Analysis (FEA) solvers for this multi-physics problem. The results of one-way and two-way coupled FSI analyses are compared with experiments and a sufficient level of accuracy is obtained. This coupling strategy could inform a fuel tank design suited to prevent structural damage due to sloshing, contributing towards the safety and longevity of the fuel tank.