AbstractCivil and military structures, such as helicopters, aircrafts, navies, tanks or buildings are exposed more and more to blast threats as both terroristic attacks in Western World and guerrilla warfare scenarios in Middle East are increasing. During an explosion the peak pressure produced by shock wave is much greater than the static collapse pressure. Metallic structures usually undergo large plastic deformations absorbing blast energy before reaching equilibrium. Due to their high specific properties, fibre-reinforced polymers are being considered for energy absorption applications in Armoured Fighting Vehicles (AFVs), where improved strategic and operational air mobility are key requirements. A deep insight into the relationship between explosion loads, composite architecture and deformation/fracture behaviour will offer the possibility to design structures with significantly enhanced energy absorption and blast resistance performance. This study examines the performance of both metallic and composite plates subjected to blast loads using commercial Finite Element Method (FEM) explicit code LS-DYNA with a particular attention to hybrid composite panels. The thesis deals with numerical 3D simulations of response caused by air blast waves generated by C-4 charges on fully clamped rectangular targets. Two different approaches have been used to simulate the blast load. Firstly CONWEP load function was applied in order to generate the blast equivalent pressure distribution on the Lagrangian plate model. The second approach considered Multi Materials Arbitrary Lagrangian Eulerian (MMALE) formulation to simulate the shock phenomenon. Numerical results have been presented and compared with the tests performed by the EUROPA Research Technology Programme (RTP) military consortium and kindly provided by QinetiQ ® showing an acceptable agreement.
|Date of Award||1 Feb 2009|
|Supervisor||Michele Meo (Supervisor)|
Blast impact simulation on composite military armours
Dolce, N. (Author). 1 Feb 2009
Student thesis: Doctoral Thesis › MPhil