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This and the next image are from:
Tomaz P. Drumond, Marcelo Greco, Carlos A. Cimini Jr. and Eduardo B. Medeiros (Department of Structural Engineering, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brasil),
“Evaluation of alternative materials in a wing fixed leading edge to support UAS impact”, Proceedings of the XL Ibero-Latin American Congress on Computational Methods in Engineering (XL CILAMCE), Natal/RN, Brazil, 11-14 November 2019
ABSTRACT: In aeronautics, the risk of an airborne impact between an aircraft and other elements such as birds, hails and other small vehicles must be evaluated. The impact of an Unmanned Aerial Systems (UAS), for example, can be more critical for an aircraft than a bird strike, as reported in a study published by the Federal Aviation Administration (FAA) in 2016. In order to make structures withstand impact with stiffener elements and minimize the increase in their weight, new aircrafts have to be reinforced with alternative materials. In the present paper, a commercial aircraft Wing Fixed Leading Edge (WFLE) reinforced with a triangular structure and other reinforced with sandwich structure made up of aluminum plies and a hexweb aluminum flexcore are subjected to an impact with an UAS. It will be verified if the lithium-ion battery from the small vehicle would penetrate into the airframe when the impact occurs at the airliner cruising speed. The UAS considered is a quadcopter configuration intended for recreational and commercial aerial photography with a 1.2 kg mass. The UAS components were proportionally increased in order to make the small vehicle to be similar to a 1.8kg bird prescribed in requirement FAR 25.571(e). The impact analyzes will be carried out using explicit finite element models of NASTRAN software. The HYPERMESH software will be used for generating finite elements mesh. The Lagrangian approach will be used to model the UAS and the WFLE. For strength analysis of WFLE skin elements will be adopted the Johnson-Cook failure model based on deformations.
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