Hybrid LES — Review and assessment
S. Vengadesan,Perumal Nithiarasu +1 more
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In this article, some of the issues involved in performing hybrid LES reported in the recent literature is briefly reviewed, as well as an alternative solu- tion suggested was to combine RANS and LES, which in general referred to as Hybrid LES.Abstract:
In the late eighties and up to the beginning of nineties computation of turbulent flows is mostly dominated by RANS (Reynolds Averaged Navier-Stokes Simulation) type modelling. During the last few years URANS (Unsteady RANS) and LES (Large Eddy Simulation) type of approaches have been attempted with some success. Yet, there have been many difficulties when LES is applied to practi- cal engineering problems and to high Reynolds number flows as energy dissipating eddies become really small and mesh resolution required for a reasonably resolved LES approaches that of DNS (Direct Numerical Simulation). An alternative solu- tion suggested was to combine RANS and LES, which in general referred to as Hybrid LES. There have been many proposals for combining RANS and LES in different ways. In this article, some of the issues involved in performing hybrid LES reported in the recent literature is briefly reviewed.read more
Citations
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Journal ArticleDOI
An hybrid RANS/LES model for simulation of complex turbulent flow
TL;DR: In this article, a nonlinear eddy viscosity model (NLEVM) and a scalable hybrid Reynolds averaged Navier-Stokes/ large eddy simulation (RANS/LES) strategy are developed to improve the capability of the EVM to simulate complex flows.
Journal ArticleDOI
Wall distance calculation using the Eikonal/Hamilton‐Jacobi equations on unstructured meshes: A finite element approach
Abstract: Purpose – The purpose of this paper is to numerically solve Eikonal and Hamilton‐Jacobi equations using the finite element method; to use both explicit Taylor Galerkin (TG) and implicit methods to obtain shortest wall distances; to demonstrate the implemented methods on some realistic problems; and to use iterative generalized minimal residual method (GMRES) method in the solution of the equationsDesign/methodology/approach – The finite element method along with both the explicit and implicit time discretisations is employed Two different forms of governing equations are also employed in the solution The Eikonal equation in its original form is used in the explicit Taylor Galerkin discretisation to save computational time For implicit method, however, the convection‐diffusion form in its conservation form is used to maintain spatial stabilityFindings – The finite element solution obtained is both accurate and smooth As expected the implicit method is much faster than the explicit method Though the
Journal ArticleDOI
Assessment of the LES-WALE and Zonal-DES Turbulence Models in Simulation of the Flow Structures around the Finite Circular Cylinder
TL;DR: In this paper, two different numerical turbulence approaches as wall adapted local eddyviscosity LES (LES-WALE) and the zonal hybrid RANS-LES approach of Detached-Eddy Simulation (Zonal-DES) are used.
Dissertation
Unsteady Aerodynamics and Adjoint Method
TL;DR: In this paper, a posteriori and a priori error estimators for both Euler and laminar Navier-Stokes flows were proposed for both 2D and 3D cases.
References
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