Airframe Water Impact Analysis Using a Local/Global Methodology

This paper describes DLR’s work concerning airframe water impact simulations based on a local/global methodology combining the explicit Finite Element Code PAM-CRASH and the hybrid impact analysis code DRI-KRASH. It is proposed to apply this methodology to a whole aircraft structure in order to prove its feasibility. In a first step, the "water" medium is calibrated in the Finite Element code with simple shape simulations (sphere, fuselage model). In a second step, Finite Element water impact analysis are performed on a representative subcomponent of an aircraft, for which the knowledge of the local behavior is determinant for the global behavior of the whole structure. Finally the Finite Element Simulation results of this sub-component are then used to generate input data for the DRI-KRASH global model of a fuselage section and of a whole aircraft instead of acquiring them exclusively from tests or from empirical methods.