Finite-Element/Boundary-Element Coupling for Inflatables: Effective Contact Resolution

Abstract

A fluid-structure interaction technique for the simulation of inflatable structures is introduced. The presented finite-element/boundary-element (FEBE) technique couples an isogeometric finite element discretization of a flexible shell structure with an isogeometric boundary element discretization of a Stokes fluid. This technique was introduced in [10] for planar problems and extended to 3D in [11]. One of the marked advantages of this approach is the contact mechanism, lubrication, which is an inherent attribute of the flow model. Its role in preventing contact was theoretically substantiated, but only demonstrated in the planar setting. In the present work, we demonstrate the effectiveness of the contact mechanism in the isogeometric and three-dimensional setting, discussing various aspects pertaining to the accurate resolution of the traction responsible for contact prevention.An extensive body of literature already covers the interface of the fields of fluidstructure interaction and contact mechanics. If the problem under consideration requires that the gap between two contact surfaces may vanish, an interface tracking technique may be applied, sometimes locally [5, 19], e.g. [3, 7, 21]. If however, a problem allows for a finite gap to be maintained between the contacting surfaces, Arbitrary Lagrangian-Eulerian [4] and Space-time [18] techniques can been used to compute problems as challenging as the disreefing of parachute clusters [15,16,17] and 1000 spheres falling through a tube [6]. In this work a finite (but arbitrarily small) gap will likewise be maintained in contact regions.The target application for the current approach is inflatable structures. These typically undergo large deformations with ubiquitous self-contact during the inflation process, which often starts from a complex, folded initial configuration. Correct simulation is contingent to the resolution of every single contact mode throughout the

Wind-structure interaction simulations of ovalling vibrations in silo groups

“…Aeronautical applications such as the flutter of airplane wings have been widely studied [76,79,80] while other applications such as parachute dynamics have also been considered in more recent years [244,245,247,250]. Practical FSI applications in the automotive industry include tyre hydroplanning [119], tyre-road noise [222] as well as airbag inflation [127,172,260]. A lot of attention has gone to biomedical applications in the FSI community because of the many interactions taking place in the human body.…”