Aeronautical Structure Impact Simulations Using a Hybrid FE/SPH Solution

Abstract

At DLR Stuttgart, one of the activities of the "Structural Integrity" Department is the modelling and simulation of aircraft structures impacting on soft soil or ditching on water. EADS/CASA is an aircraft manufacturer with capabilities to build complete aircraft. The aim of structural dynamics studies by DLR and CASA is to assess the damage and structural integrity in real crash events. They are crucial for the development and certification of aircraft structures. Impact phenomena to be studied include bird strike, propeller blade loss, ice impact, vulnerability for projectile impact on fuel tanks, and ditching. A key instrument in the success to tackle these challenges has been the emergence of software tools based on the Finite Element Method (FEM) technique, like PAM-CRASH from ESI-Group. One of the milestones in recent numerical simulations has been the introduction of the Smoothed Particle Hydrodynamics method that allows proper modelling of a bird and of impacted liquids. The first validation of the numerical methodology has been achieved through a series of vertical impact cases with known test results that were analyzed in-depth by DLR.