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ARTICLE
Hybrid LES/URANS Simulation of Rayleigh-Bénard Convection Using BEM
Primož Kocutar1, *, Jure Ravnik1, Leopold Škerget1
1 Faculty of Mechanical Engineering, University of Maribor, Smetanova 17, SI-2000 Maribor, Slovenia.
∗ Corresponding Author: Primož Kocutar. Email: .
Computer Modeling in Engineering & Sciences 2020, 123(1), 1-22. https://doi.org/10.32604/cmes.2020.08728
Received 01 October 2019; Accepted 19 December 2019; Issue published 01 April 2020
Abstract
In this paper, we develop and test a unified hybrid LES/URANS turbulence
model with two different Large Eddy Simulation (LES) turbulence models. The numerical
algorithm is based on the Boundary Element Method. In the existing hybrid LES/URANS
turbulence model we implemented a new Smagorinsky LES turbulence model. The
hybrid LES/URANS turbulence model is unified, which means that the LES/URANS
interface is changed dynamically during simulation using a physical quantity. In order
to define the interface between LES and unsteady Reynolds Averaged Navier Stokes
(URANS) zones during the simulation, we use the Reynolds number based on turbulent
kinetic energy as a switching criterion. This means that the flow characteristics define
where the sub-grid scale or URANS effective viscosity and thermal conductivity are
used in the governing equations in the next time step. In unified hybrid turbulence
models, only one set of governing equations is used for LES and URANS regions.
The developed hybrid LES/URANS model was tested on non-isothermal, unsteady and
turbulent Rayleigh-Bénard Convection and compared with an existing model, where LES
is based on turbulent kinetic energy. The hybrid turbulence model was implemented within
a numerical algorithm based on the Boundary-Domain Integral Method, where a single
domain and sub-domain approaches were used. The numerical algorithm uses governing
equations written in a velocity-vorticity form. The false transient time scheme is used for
the kinematics equation.
Keywords
Cite This Article
APA Style
Kocutar, P., Ravnik, J., Škerget, L. (2020). Hybrid LES/URANS simulation of rayleigh-bénard convection using BEM. Computer Modeling in Engineering & Sciences, 123(1), 1-22. https://doi.org/10.32604/cmes.2020.08728
Vancouver Style
Kocutar P, Ravnik J, Škerget L. Hybrid LES/URANS simulation of rayleigh-bénard convection using BEM. Comput Model Eng Sci. 2020;123(1):1-22 https://doi.org/10.32604/cmes.2020.08728
IEEE Style
P. Kocutar, J. Ravnik, and L. Škerget "Hybrid LES/URANS Simulation of Rayleigh-Bénard Convection Using BEM," Comput. Model. Eng. Sci., vol. 123, no. 1, pp. 1-22. 2020. https://doi.org/10.32604/cmes.2020.08728