CRASHWORTHINESS ASSESSMENT IN AIRCRAFT DITCHING INCIDENTS

摘要

In this paper, a comparative study has beenperformed between the Meshless Lagrangianand Coupled Lagrangian-Eulerian schemes, toevaluate their overall efficiency andeffectiveness for analyzing fluid-structureinteractive systems. Soft body impact eventsonto composite laminates representing primaryand secondary aircraft structures have beenstudied. Several cases with different birdvelocities have been simulated to observe thenon-linier behavior of soft body impact, alongwith the shortcomings of the modelingmethodologies applied. The MeshlessLagrangian model produced a higher initialpeak force, whereas the Coupled Lagrangian-Eulerian approach captured the impact windowmore smoothly with less obvious spikes. Theseschemes have also been compared with theconventional Lagrangian approach, whichproved to be less accurate due to high meshdistortion and loss of mass from erosion. Thestudy was further extended to analyze birdstrikeon a composite wing leading-edge. Withvalidation from experimental results, thedeveloped modeling methodology was also usedto analyze other fluid-structure interactivesystems such as structural damage caused byaircraft ditching over water.