Journal ArticleDOI
Reassessment of the scale-determining equation for advanced turbulence models
TLDR
In this paper, a two-equation turbulence model is proposed that is shown to be quite accurate for attached boundary layers in adverse pressure gradient, compressible boundary layers, and free shear flows.Abstract:
A comprehensive and critical review of closure approximations for two-equation turbulence models has been made. Particular attention has focused on the scale-determining equation in an attempt to find the optimum choice of dependent variable and closure approximations. Using a combination of singular perturbation methods and numerical computations, this paper demonstrates that: 1) conventional A:-e and A>w formulations generally are inaccurate for boundary layers in adverse pressure gradient; 2) using "wall functions'' tends to mask the shortcomings of such models; and 3) a more suitable choice of dependent variables exists that is much more accurate for adverse pressure gradient. Based on the analysis, a two-equation turbulence model is postulated that is shown to be quite accurate for attached boundary layers in adverse pressure gradient, compressible boundary layers, and free shear flows. With no viscous damping of the model's closure coefficients and without the aid of wall functions, the model equations can be integrated through the viscous sublayer. Surface boundary conditions are presented that permit accurate predictions for flow over rough surfaces and for flows with surface mass addition.read more
Citations
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Journal ArticleDOI
Two-equation eddy-viscosity turbulence models for engineering applications
TL;DR: In this paper, two new two-equation eddy-viscosity turbulence models are presented, which combine different elements of existing models that are considered superior to their alternatives.
Proceedings ArticleDOI
A one-equation turbulence model for aerodynamic flows
Philippe R. Spalart,S. Allmaras +1 more
Book
Computational Fluid Dynamics: Principles and Applications Ed. 3
TL;DR: This updated edition includes new worked programming examples, expanded coverage and recent literature regarding incompressible flows, the Discontinuous Galerkin Method, the Lattice Boltzmann Method, higher-order spatial schemes, implicit Runge-Kutta methods and code parallelization.
NEMO ocean engine
TL;DR: The ocean engine of NEMO (Nucleus for European Modelling of the Ocean) is a primitive equation model adapted to regional and global ocean circulation problems as discussed by the authors, which is intended to be a flexible tool for studying the ocean and its interactions with the others components of the earth climate system over a wide range of space and time scales.
Journal ArticleDOI
Formulation of the k-w Turbulence Model Revisited
TL;DR: In this article, a reformulated version of the author's k-ω model of turbulence has been presented, which has been applied to both boundary layers and free shear flows and has little sensitivity to finite freestream boundary conditions on turbulence properties.
References
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Journal ArticleDOI
The prediction of laminarization with a two-equation model of turbulence
W.P. Jones,Brian Launder +1 more
TL;DR: In this article, the local turbulent viscosity is determined from the solution of transport equations for the turbulence kinetic energy and the energy dissipation rate, and the predicted hydrodynamic and heat-transfer development of the boundary layers is in close agreement with the measured behaviour.
The Structure of Turbulence in Fully Developed Pipe Flow
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Journal ArticleDOI
Calculation of boundary-layer development using the turbulent energy equation
TL;DR: In this article, the turbulent energy equation is converted into a differential equation for the turbulent shear stress by defining three empirical functions relating the turbulent intensity, diffusion and dissipation to the stress profile.
Proceedings ArticleDOI
A Numerical Method for Solving the Equations of Compressible Viscous Flow
TL;DR: In this paper, a second-order accurate method for solving viscous flow equations has been proposed that preserves conservation form, requires no block or scalar tridiagonal inversions, is simple and straightforward to program (estimated 10% modification for the update of many existing programs), and should easily adapt to current and future computer architectures.
Journal ArticleDOI
A model for inhomogeneous turbulent flow
TL;DR: In this paper, a set of model equations is given to describe the gross features of a statistically steady or slowly varying inhomogeneous field of turbulence and the mean velocity distribution, based on the idea that turbulence can be characterized by "densities" which obey nonlinear diffusion equations.