Fluid-structure interaction in crash simulation

In the automotive industry crash simulation plays an important role in decreasing development costs and in improving cars. To increase the reliability of crash simulation the modelling of parts of vehicles, which has been neglected in the past, becomes more important. One of these parts is the fuel tank together with the fuel inside the tank. An important aspect of a fuel tank in crash simulation is its kinematic behaviour as a result of the interaction with the fuel. To obtain good results in the simulation it is necessary to take into consideration the fluid properties of the fuel. The ability of crash simulation software to model fluid-structure interaction including free surfaces has been limited until now. Therefore, it is helpful to obtain some insight into modelling capabilities and to compare them with other sophisticated simulation techniques. In this paper three modelling techniques for fluid-structure interaction of fluids with free surfaces are presented. These results are compared with an experiment. It is shown that the simplest modelling technique is precise enough for reliable crash simulations.