A computationally efficient 3D finite-volume scheme for violent liquid–gas sloshing

Abstract

We describe a semi-implicit volume-of-fluid free-surface-modelling methodology for flow problems involving violent free-surface motion. For efficient computation, a hybrid-unstructured edge-based vertex-centred finite volume discretisation is employed, while the solution methodology is entirely matrix free. Pressures are solved using a matrix-free preconditioned generalised minimum residual algorithm and explicit time-stepping is employed for the momentum and interface-tracking equations. The high resolution artificial compressive (HiRAC) volume-of-fluid method is used for accurate capturing of the free surface in violent flow regimes while allowing natural applicability to hybrid-unstructured meshes. The code is parallelised for solution on distributed-memory architectures and evaluated against 2D and 3D benchmark problems. Good parallel scaling is demonstrated, with almost linear speed-up down to 6000 cells per core. Finally, the code is applied to an industrial-type problem involving resonant excitation of a fuel tank, and a comparison with experimental results is made in this violent sloshing regime.