IRENE: a fluId layeR finitE-elemeNt softwarE

TL;DR

IRENE is a versatile finite-element software library designed for simulating the complex dynamics of viscous fluid layers in three-dimensional space, accommodating various boundary conditions and physical regimes.

Contribution

It introduces a novel finite-element library capable of handling open surfaces with obstacles and diverse physical regimes, built on the FEniCS platform.

Findings

Successfully validated against analytical and numerical results.

Demonstrated capability through multiple physical examples.

Applicable across multiple physical scales from microscopic to planetary.

Abstract

We present a finite-element software library, IRENE, which allows to solve numerically the dynamics of a viscous fluid layer embedded in three-dimensional space. Unlike finite-element libraries present in the literature, IRENE can handle two-dimensional open surfaces with a wide range of boundary conditions, and inter-surface obstacles with any shapes, 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.