The Experts below are selected from a list of 79977 Experts worldwide ranked by ideXlab platform
Arne V. Johansson - One of the best experts on this subject based on the ideXlab platform.
-
Study of Transitions in the Atmospheric Boundary Layer Using Explicit Algebraic Turbulence Models
Boundary-Layer Meteorology, 2016Co-Authors: Werner Lazeroms, Stefan Wallin, Gunilla Svensson, Eric Bazile, Geert Brethouwer, Arne V. JohanssonAbstract:Study of transitions in the atmospheric boundary layer using explicit algebraic Turbulence Models.
-
engineering Turbulence Models and their development with emphasis on explicit algebraic reynolds stress Models
2002Co-Authors: Arne V. JohanssonAbstract:Single-point Turbulence Models will be discussed from a somewhat analytical point of view. The lowest level of modelling considered here is that of eddy-viscosity-based two-equation Models, but particular attention is given to explicit algebraic Reynolds stress Models (and explicit algebraic scalar flux Models). Some new trends in Models based directly on the Reynolds stress transport equations are also discussed.
Stefan Wallin - One of the best experts on this subject based on the ideXlab platform.
-
Study of Transitions in the Atmospheric Boundary Layer Using Explicit Algebraic Turbulence Models
Boundary-Layer Meteorology, 2016Co-Authors: Werner Lazeroms, Stefan Wallin, Gunilla Svensson, Eric Bazile, Geert Brethouwer, Arne V. JohanssonAbstract:Study of transitions in the atmospheric boundary layer using explicit algebraic Turbulence Models.
-
assessment of explicit algebraic reynolds stress Turbulence Models in aerodynamic computations
Aerospace Science and Technology, 2005Co-Authors: Martin Franke, Stefan Wallin, Frank ThieleAbstract:In the aerodynamic industrial design process, the use of numerical simulation, including viscous effects, is of ever increasing importance. As simple, standard Boussinesq-viscosity Turbulence Models have proven insufficient to correctly predict complex flow situations, attention is drawn to more reliable approaches towards the modelling of Turbulence. This work aims at assessing the potential of Explicit Algebraic Reynolds Stress Models (EARSM) for application-oriented aerodynamic computations. To this end, two different EARSM are investigated on a variety of configurations in sub- and transonic steady flow, ranging from 2D aerofoils to 3D wing/body-configurations. Is is demonstrated that an increased over-all simulation quality is achieved. Thus, while their overhead with respect to standard linear approaches remains limited, EARSM constitute a valuable extension to the model range available to the aerodynamic design engineer.
Virginia A Williams - One of the best experts on this subject based on the ideXlab platform.
-
a systematic comparison of two equation reynolds averaged navier stokes Turbulence Models applied to shock cloud interactions
Monthly Notices of the Royal Astronomical Society, 2017Co-Authors: Matthew D Goodson, Fabian Heitsch, Karl Eklund, Virginia A WilliamsAbstract:Turbulence Models attempt to account for unresolved dynamics and diffusion in hydrodynamical simulations. We develop a common framework for two-equation Reynolds-Averaged Navier-Stokes (RANS) Turbulence Models, and we implement six Models in the Athena code. We verify each implementation with the standard subsonic mixing layer, although the level of agreement depends on the definition of the mixing layer width. We then test the validity of each model into the supersonic regime, showing that compressibility corrections can improve agreement with experiment. For Models with buoyancy effects, we also verify our implementation via the growth of the Rayleigh-Taylor instability in a stratified medium. The Models are then applied to the ubiquitous astrophysical shock-cloud interaction in three dimensions. We focus on the mixing of shock and cloud material, comparing results from Turbulence Models to high-resolution simulations (up to 200 cells per cloud radius) and ensemble-averaged simulations. We find that the Turbulence Models lead to increased spreading and mixing of the cloud, although no two Models predict the same result. Increased mixing is also observed in inviscid simulations at resolutions greater than 100 cells per radius, which suggests that the turbulent mixing begins to be resolved.
Werner Lazeroms - One of the best experts on this subject based on the ideXlab platform.
-
Study of Transitions in the Atmospheric Boundary Layer Using Explicit Algebraic Turbulence Models
Boundary-Layer Meteorology, 2016Co-Authors: Werner Lazeroms, Stefan Wallin, Gunilla Svensson, Eric Bazile, Geert Brethouwer, Arne V. JohanssonAbstract:Study of transitions in the atmospheric boundary layer using explicit algebraic Turbulence Models.
Matthew D Goodson - One of the best experts on this subject based on the ideXlab platform.
-
a systematic comparison of two equation reynolds averaged navier stokes Turbulence Models applied to shock cloud interactions
Monthly Notices of the Royal Astronomical Society, 2017Co-Authors: Matthew D Goodson, Fabian Heitsch, Karl Eklund, Virginia A WilliamsAbstract:Turbulence Models attempt to account for unresolved dynamics and diffusion in hydrodynamical simulations. We develop a common framework for two-equation Reynolds-Averaged Navier-Stokes (RANS) Turbulence Models, and we implement six Models in the Athena code. We verify each implementation with the standard subsonic mixing layer, although the level of agreement depends on the definition of the mixing layer width. We then test the validity of each model into the supersonic regime, showing that compressibility corrections can improve agreement with experiment. For Models with buoyancy effects, we also verify our implementation via the growth of the Rayleigh-Taylor instability in a stratified medium. The Models are then applied to the ubiquitous astrophysical shock-cloud interaction in three dimensions. We focus on the mixing of shock and cloud material, comparing results from Turbulence Models to high-resolution simulations (up to 200 cells per cloud radius) and ensemble-averaged simulations. We find that the Turbulence Models lead to increased spreading and mixing of the cloud, although no two Models predict the same result. Increased mixing is also observed in inviscid simulations at resolutions greater than 100 cells per radius, which suggests that the turbulent mixing begins to be resolved.
