Abstract

External airframe structural components facing the aircraft flight direction, are prone to bird collisions. Aircraft manufacturers meet the bird strike airworthiness requirements through physical bird strike testing. Mainly due to the high costs involved in the certification process, recent studies have highlighted the capabilities and benefits of hybrid simulationexperiment techniques that reduce certification costs. The numerical investigation presented herein, studied the bird-strike simulation methodologies implemented to support airframe manufacturers to partially fulfill the current certification airworthiness requirements. The methodology can be also applied during preliminary aircraft parametric design stages. In the current study, the method was applied onto an aircraft wing leading edge preliminary design, which led to design exploration by correlating the leading edge skin materials and thicknesses with the rib pitch positioning. The bird-strike impact model was simulated using the Smoothed Particle Hydrodynamics numerical method using ABAQUS® Explicit finite element package. The materials benchmarked were aluminum alloy 2024-T3, carbon fiber reinforced epoxy IM7/8552 and S2 glass Fiber Metal Laminate GLARE®. The design goal of the case study was to provide with preliminary evidence for impact resistance, quantified as residual permanent structural deformation of the critical structural components for which design charts were drawn and presented herein. 

Abstract

Abstract

This work extends a multi-phase mixing model framework designed for a Smoothed Particle Hydrodynamics context. Specifically, we propose a higher-order variation using the first-order accurate Generalised Finite Difference differential operators to construct an incompressible scheme for simulating fluid-solid coupled systems resolved via a continuum mixture model. The proposed scheme incorporates inter-phase shear between phases and the viscosity dependency of the solid phase concentration. The scheme is verified by simulating a modified lid-driven cavity case at Re = 1000. In this simulation, our method was capable of treating initially discontinuous concentration fields with a maximum solid volume concentration of 0.5 and a solid-to-fluid density ratio of 4.