Advances in Numerical Ditching Simulation of Flexible Aircraft Models

Abstract

This paper deals with explicit numerical simulation of fixed-wing aircraft ditching using a coupled approach of Smoothed Particle Hydrodynamics and Finite Elements. Particular focus is put on recent advances toward simulation of flexible full aircraft models, which comprises significant challenges with respect to the numerical efficiency as well as the model complexity. First, the pursued numerical ap- proach is briefly presented. In order to deal with aforementioned challenges, an automated modular tool, which generates numerical models and launches ditching simulations, is presented. The paper provides a brief explanation of state-of-the-art aircraft as well as fluid modeling techniques used and furthermore presents an integrated model that computes aerodynamic loads during the simulation. The developed tool is used to conduct various numerical studies. First, the improved efficiency of such simulations over the state of the art is shown. Next, results of parameter studies are presented, demon- strating the effects of impact conditions on the aircraft motion. Finally, the structural deformation experienced during ditching of a detailed finite element aircraft model is analyzed and its effects on the aircraft motion are discussed.