Naslov
FINITE VOLUME IMMERSED BOUNDARY METHOD FOR TURBULENT FLOW SIMULATIONS

Autori
Jasak, Hrvoje ; Rigler, Damir ; Tuković, Željko

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, pp prezentacija, znanstveni

Skup
9th OpenFOAM Workshop

Mjesto i datum
Zagreb, Hrvatska, 23.06.2014. - 26.06.2014

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
Immersed Boundary Method; Cell-centred Finite Volume Method; RANS; Wall Functions

Sažetak
The distinguishing feature of the immersed boundary method (IBM) is that the simulation of the flow around or inside immersed boundary is carried out on a computa- tional mesh which does not conform to the boundary shape. The procedure for imposition of boundary conditions at the immersed boundary is what distinguishes one IBM from another. This article presents OpenFOAM implementation of an IBM in the cell-centred finite volume framework based on the so called ”discrete forcing approach” [1] with direct imposition of boundary conditions. The so called immersed boundary cells are identified as fluid cells cut by the immersed boundary and boundary condition is imposed at these cells by modifying discretised transport equation. Dirichlet and neumann boundary condi- tions are imposed using quadratic interpolation where unknown coefficient are determined by weighted least square method on extended stencil. Special care is taken to preserve global mass conservation property of the numerical solution by properly scaling fluxes through the face-cage enclosing immersed boundary. Proposed implementation of the IBM supports polyhedral background meshes and local mesh refinement. For turbulent flow simulations using RANS turbulence models, a special wall function are implemented. The IBM implementation is validated with four test cases that cover transient and steady- state, laminar and turbulent, single phase and free surface two-phase flow. Both integral values (such as force on the object) and certain fields (such as pressure, or free surface) are compared with experimental results from literature and show satisfactory agreement.

Izvorni jezik
Engleski

Znanstvena područja
Strojarstvo

POVEZANOST RADA