IRENE: a fluId layeR finitE-elemeNt softwarE
Description
We present a finite element (FE) software library, IRENE, which allows for numerically solving the dynamics of a viscous fluid layer embedded in three-dimensional space. IRENE describes two-dimensional, dynamical open surfaces, and it is restricted to manifolds described with the Monge gauge. IRENE supports a wide range of boundary conditions and shapes of inter-surface obstacles, and is built upon the user-friendly and versatile finite element computational software (FEniCS). Also, the library can describe a wide range of physical regimes—both low-Reynolds-number and inertia-dominated ones—capturing the complex coupling between in-plane flows, out-of-plane deformations, surface tension, and elastic response. We validate IRENE against known analytical and numerical results, and demonstrate its capabilities through physical examples. Overall, IRENE provides a versatile and efficient tool for understanding fluid-layer dynamics on multiple physical scales, from flows of lipidic membranes on a microscopic level, to fluid flows on a macroscopic scale, to atmospheric air flows on a planetary level.