Simulation of shock wave impactdue to explosion on a flying, flexible aircraft

This paper describes the results obtained by a computational simulation of the impact of shock waves due to explosion on a flying flexible aircraft of commercial type. An explicit three-dimensional dynamic nonlinear coupled analysis has been conducted by means of the software MSC.Dytran. A Lagrangian mesh has been used for the structural parts, and a Eulerian domain is used for the surrounding fluid. The fluiddynamic solver uses a Eulerian approach and employs a finite volume method to discretize the governing equations. Structural elements are discretized by the Finite Element Method. The impact of the related shock waves on a simple panel and a wing box has been considered. The vibration of an aircraft as a whole, caused by its flexibility, has been analyzed. The analysis has mainly shown that the conducted investigation can be used to evaluate the loads on the aircraft for various initial positions of the explosion as well as for various amounts of the explosive charge. The method could permit a better design of the aircraft with respect to explosion phenomena and simulation of aircraft accidents, aimed at understanding their causes.