Partitioned finite element analysis of shell structures under blast waves propagation
Allan Yoshio Suzuki1; Jeferson Wilian Dossa Fernandes1; Rodolfo André Kuche Sanches1
1 Universidade de São Paulo - Escola de Engenharia de São Carlos
doi:10.20906/CPS/CILAMCE2015-0592
Resumo
In this work we study fluid-structure coupling of short duration events, such as blast waves. During such problems, a large amount of energy is liberated in a very localized way, producing a region of high pressure expanding supersonically, followed by a subsonic flow. In order to have a good comprehension of such effects, it is necessary to carry an analysis not only considering the estimated impact forces over the structure, but also the coupling between fluid flow and the deformable structure. In this work we explore how to couple a compressible fluid dynamics solver to a nonlinear shell dynamics solver in order to precisely model these problems. One-way and two-way partitioned coupling techniques are considered and different time steps are allowed to fluid and structure. The fluid flow is modeled by linear tetrahedral finite elements using an explicit time integrator using arbitrary Lagrangian Eulerian description, while the structure is modeled by shell elements using a energy functional Lagrangian formulation with positions as nodal parameters instead of displacement, allowing to employ the implicit Newmark time integrator for large displacement problems. A couple numerical examples are used to analyse the effect of time step and different coupling algorithm os results.
Palavras-chave: Fluid Structure Interaction; Nonlinear shell dynamics; Blast waves; Partitioned coupling