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Compressible Large Eddy Simulation Using Unstructured Grid: Supersonic Boundary Layer And Compression Ramps
, 2000
"... A Mach 3 adiabatic at plate turbulent boundary layer at Re = 2 10 4 is studied using the Monotone Integrated Large Eddy Simulation (MILES) method. The Favreltered compressible NavierStokes equations are solved on a threedimensional unstructured grid of tetrahedral cells. A variable limiter den ..."
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Cited by 23 (2 self)
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A Mach 3 adiabatic at plate turbulent boundary layer at Re = 2 10 4 is studied using the Monotone Integrated Large Eddy Simulation (MILES) method. The Favreltered compressible NavierStokes equations are solved on a threedimensional unstructured grid of tetrahedral cells. A variable limiter denoted the extremum limiter is developed to control the overshoots caused by high order interpolation. The statistical predictions computed with and without the limiter are compared with experimental data and Direct Numerical Simulation (DNS). Results for 8 and 25 compression corners at Mach 3 and Re = 2 10 4 are compared with experimental data. 1 Introduction High order Total Variation Diminishing (TVD) schemes have been developed in one dimension into reliable tools for numerical prediction of the solution of hyperbolic systems of equations. However, in higher dimensions it has proved dicult to obtain the same degree of robustness and accuracy with extensions of these one dim...
A Cost/Benefit Analysis of Simplicial Mesh Improvement Techniques as Measured by Solution Efficiency
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Computational Study Of The Effect Of Unstructured Mesh Quality On Solution Efficiency
 Presented at the 13 th Annual Computational Fluid Dynamics Meeting, Snowmass Village
, 1997
"... It is well known that mesh quality affects both efficiency and accuracy of CFD solutions. Meshes with distorted elements make solutions both more difficult to compute and less accurate. In this article, we review a recently proposed technique for improving mesh quality as measured by element angle ( ..."
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It is well known that mesh quality affects both efficiency and accuracy of CFD solutions. Meshes with distorted elements make solutions both more difficult to compute and less accurate. In this article, we review a recently proposed technique for improving mesh quality as measured by element angle (dihedral angle in three dimensions) using a combination of optimizationbased smoothing techniques and local reconnection schemes. Typical results that quantify mesh improvement for a number of application meshes are presented. We then examine effects of mesh quality as measured by the maximum angle in the mesh on the convergence rates of the commonly used GMRES and Multigrid solvers. Numerical experiments are performed that quantify the cost and benefit of using mesh optimization schemes for incompressible and weakly compressible flow over a cylinder.
Large Eddy Simulation Of Compressible Flows Using Unstructured Grids
"... An algorithm for compressible Large Eddy Simulation (LES) using unstructured tetrahedral grids is presented. The subgrid scale stresses are represented by two approaches: the Monotone Integrated Large Eddy Simulation (MILES) technique of Boris, Oran and Grinstein, whereby the energy transfer from th ..."
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Cited by 1 (1 self)
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An algorithm for compressible Large Eddy Simulation (LES) using unstructured tetrahedral grids is presented. The subgrid scale stresses are represented by two approaches: the Monotone Integrated Large Eddy Simulation (MILES) technique of Boris, Oran and Grinstein, whereby the energy transfer from the resolved scales to the subgrid scales is modeled using the inherent dissipation of the numerical algorithm, and a hybrid technique combining MILES with a Smagorinsky eddy viscosity model for the subgrid scale stresses. The algorithm is efficiently parallelized using MPI. Results are presented for the simulation of the decay of incompressible isotropic turbulence. Good agreement is obtained with the experimental data of ComteBellot and Corrsin for the decay of turbulence energy, and reasonable agreement with the temporal evolution of the energy spectrum. 1 Introduction Current Reynoldsaveraged NavierStokes (RANS) simulation methodology for high speed turbulent flows lacks important capa...
POLYNOMIAL LEASTSQUARES RECONSTRUCTION FOR SEMILAGRANGIAN CELLCENTERED HYDRODYNAMIC SCHEMES
"... Abstract. In Inertial Confinement Fusion (ICF) simulation, use of Lagrangian hydrodynamic numerical schemes is a cornerstone. It avoids mixing of materials and allows for symmetry preservation in dimension two. Recently, [7] and then [9] proposed an interesting alternative to the historical VNR sch ..."
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Abstract. In Inertial Confinement Fusion (ICF) simulation, use of Lagrangian hydrodynamic numerical schemes is a cornerstone. It avoids mixing of materials and allows for symmetry preservation in dimension two. Recently, [7] and then [9] proposed an interesting alternative to the historical VNR scheme [15]. These two first order schemes are multidimensional generalizations of the Godunov acoustic solver. Alternatively, a WENO Lagrangian scheme was proposed in [6]. This scheme suffers from nonpreservation of symmetries and its velocity computation can be discussed. The aim of this work is to evaluate the later scheme on ICF representative test cases and to derive a polynomial reconstruction that preserves symmetries for the three cellcentered scheme. This reconstruction is inspired by [12]. Since this paper focuses on the approximation of Euler equations, considered test cases are purely hydrodynamic and do not illustrate all difficulties encountered in ICF. We first briefly recall different schemes used for this study. We then explain the LeastSquares ENO reconstruction that we chose for symmetry preservation and describe the limiting strategy. We finally illustrates the presented results by some representative numerical experiments. Résumé. La simulation de Fusion par Confinement Inertiel (FCI) utilise souvent des schémas hydrodynamiques Lagrangiens. Cela permet d’éviter le mélange de matériaux et permet de préserver