A new volume-of-fluid method in openfoam

Johan Roenby, Bjarke Eltard Larsen, Henrik Bredmose, Hrvoje Jasak

Publikation: Bidrag til bog/antologi/rapportKonferencebidrag i proceedingsForskningpeer review

Abstract

To realise the full potential of Computational Fluid Dynamics (CFD) within marine science and engineering, there is a need for continuous maturing as well as verification and validation of the numerical methods used for free surface and interfacial flows. One of the distinguishing features here is the existence of a water surface undergoing large deformations and topological changes during transient simulations e.g. of a breaking wave hitting an offshore structure. To date, the most successful method for advecting the water surface in marine applications is the Volume-of-Fluid (VOF) method. While VOF methods have become quite advanced and accurate on structured meshes, there is still room for improvement when it comes to unstructured meshes of the type needed to simulate flows in and around complex geometric structures. We have recently developed a new geometric VOF algorithm called isoAdvector for general meshes and implemented it in the OpenFOAM interfacial flow solver called interFoam. We have previously shown the advantages of isoAdvector for simple pure advection test cases on various mesh types. Here we test the effect of replacing the existing interface advection method in interFoam, based on MULES limited interface compression, with the new isoAdvector method. Our test case is a steady 2D stream function wave propagating in a periodic domain. Based on a series of simulations with different numerical settings, we conclude that the introduction of isoAdvector has a significant effect on wave propagation with interFoam. There are several criteria of success: Preservation of water volume, of interface sharpness and shape, of crest kinematics and celerity, not to mention computational efficiency. We demonstrate how isoAdvector can improve on many of these parameters, but also that the success depends on the solver setup. Thus, we cautiously conclude that isoAdvector is a viable alternative to MULES when set up correctly, especially when interface sharpness, interface smoothness and calculation times are important. There is, however, still potential for improvement in the coupling of isoAdvector with interFoam's PISO based pressure-velocity solution algorithm.

OriginalsprogEngelsk
Titel7th International Conference on Computational Methods in Marine Engineering, MARINE 2017
RedaktørerPatrick Queutey, David Le Touze, Michel Visonneau
Antal sider12
ForlagInternational Center for Numerical Methods in Engineering
Publikationsdato2017
Sider266-277
ISBN (Elektronisk)9788494690983
StatusUdgivet - 2017
Udgivet eksterntJa
Begivenhed7th International Conference on Computational Methods in Marine Engineering, MARINE 2017 - Nantes, Frankrig
Varighed: 15 maj 201717 maj 2017

Konference

Konference7th International Conference on Computational Methods in Marine Engineering, MARINE 2017
Land/OmrådeFrankrig
ByNantes
Periode15/05/201717/05/2017
Navn7th International Conference on Computational Methods in Marine Engineering, MARINE 2017
Vol/bind2017-May

Bibliografisk note

Funding Information:
This work was funded by JR's Sapere Aude: DFF-Research Talent grant from The Danish Council for Independent Research | Technology and Production Sciences (Grant DFF-1337-00118) and by DHI's GTS grant from the Danish Agency for Science, Technology and Innovation.

Emneord

  • CFD
  • Interfacial flows
  • IsoAdvector
  • Marine engineering
  • Surface gravity waves
  • VOF methods

Citer dette