Diese Website verwendet Cookies. Mit der Nutzung der Website stimmen Sie deren Verwendung zu. Weitere Informationen erhalten Sie in unserer Datenschutzerklärung.

Hail Impact Problem in Aeronautical Field

Crashworthiness is one of the aspects that must be taken into account till the design phase, especially in aeronautical field. Some bodies, impacting against structures, can be considered as soft body. Soft bodies are highly deformable and flow over the structure spreading the impact load. Among them, hail impact can be considered as one of the most dangerous event during the operative life of aircrafts. Damage caused by hail stones, especially onto composite structures, can create barely visible effects, extremely dangerous for the structures. Despite the great progress in FE codes, the analyses of soft body impact events are in many cases out of reach. Finite element (FE) codes adopt Lagrangian approach. This approach suffers mesh distortion that may lead to inaccuracy and premature termination of the analyses. Smoothed particle hydrodynamic (SPH) technique based on an interpolatory solution of the balance equations was introduced to overcome this limits of the Lagrangian FEM. SPH approach comes with a number of drawbacks and therefore for many applications the traditional Lagrangian FE approach is preferred. Nowadays some explicit codes (e.g. Pamcrash and LS-Dyna) implement a rather sophisticate approach that aims at combining the benefit of these two techniques. This approach consists of switching from the FE to the SPH approach when the distortion of the FE mesh becomes such to cause inaccuracy or premature termination of the analyses. In this paper a hail impact study has been proposed. A numerical investigation of the phenomenon has been done considering all these approaches. Experimental tests have also been performed to assess numerical methods performances in terms of impact dynamics and loads. As a result of this investigation, benefits and drawbacks of the FE to SPH approach have been highlighted.