Journal ArticleDOI
A dynamic subgrid‐scale eddy viscosity model
TLDR
In this article, a new eddy viscosity model is presented which alleviates many of the drawbacks of the existing subgrid-scale stress models, such as the inability to represent correctly with a single universal constant different turbulent fields in rotating or sheared flows, near solid walls, or in transitional regimes.Abstract:
One major drawback of the eddy viscosity subgrid‐scale stress models used in large‐eddy simulations is their inability to represent correctly with a single universal constant different turbulent fields in rotating or sheared flows, near solid walls, or in transitional regimes. In the present work a new eddy viscosity model is presented which alleviates many of these drawbacks. The model coefficient is computed dynamically as the calculation progresses rather than input a priori. The model is based on an algebraic identity between the subgrid‐scale stresses at two different filtered levels and the resolved turbulent stresses. The subgrid‐scale stresses obtained using the proposed model vanish in laminar flow and at a solid boundary, and have the correct asymptotic behavior in the near‐wall region of a turbulent boundary layer. The results of large‐eddy simulations of transitional and turbulent channel flow that use the proposed model are in good agreement with the direct simulation data.read more
Citations
More filters
Journal ArticleDOI
On the magnitude and variability of subgrid-scale eddy-diffusion coefficients in the atmospheric surface layer
TL;DR: In this article, a field study [Horizontal Arrays Turbulence Study (HATS)] specifically designed to measure turbulence quantities of interest in LES, such as the parameter cs, is conducted.
Journal ArticleDOI
A scale-aware subgrid model for quasi-geostrophic turbulence
TL;DR: Bachman et al. as mentioned in this paper introduced two methods for dynamically prescribing eddy-induced diffusivity, advection, and vis6 cosity appropriate for primitive equation models with resolutions permitting the forward potential enstrophy 7 cascade of quasigeostrophic dynamics.
Journal ArticleDOI
Flow characteristics and thermal performance in chevron type plate heat exchangers
Jonghyeok Lee,Kwan-Soo Lee +1 more
TL;DR: In this article, an unsteady numerical analysis using large-eddy simulation (LES) was performed to investigate the fluid flow in chevron-type plate heat exchangers.
Journal ArticleDOI
Preferential concentration and relative velocity statistics of inertial particles in Navier-Stokes turbulence with and without filtering
Baidurja Ray,Lance R. Collins +1 more
TL;DR: In this paper, the radial distribution function (RDF) and the relative velocity measured along the line-of-centres of two particles are the key statistical inputs to the collision kernel for finite-inertia particles suspended in a turbulent flow.
Journal ArticleDOI
Effects of a three-dimensional hill on the wake characteristics of a model wind turbine
TL;DR: In this paper, the authors studied the spatial evolution of a turbine wake downwind of a three-dimensional sinusoidal hill using large-eddy simulations and wind tunnel measurements, and the effect of the hill turbine spacing was investigated through a comparative analysis with the turbine wake results in the undisturbed turbulent boundary layer.
References
More filters
Journal ArticleDOI
General circulation experiments with the primitive equations
TL;DR: In this article, an extended period numerical integration of a baroclinic primitive equation model has been made for the simulation and the study of the dynamics of the atmosphere's general circulation, and the solution corresponding to external gravitational propagation is filtered by requiring the vertically integrated divergence to vanish identically.
Journal ArticleDOI
Turbulence statistics in fully developed channel flow at low reynolds number
TL;DR: In this article, a direct numerical simulation of a turbulent channel flow is performed, where the unsteady Navier-Stokes equations are solved numerically at a Reynolds number of 3300, based on the mean centerline velocity and channel half-width, with about 4 million grid points.
Journal ArticleDOI
Renormalization group analysis of turbulence I. Basic theory
Victor Yakhot,Steven A. Orszag +1 more
TL;DR: In this article, a dynamic renormalization group (RNG) method for hydrodynamic turbulence was developed, which uses dynamic scaling and invariance together with iterated perturbation methods, allowing us to evaluate transport coefficients and transport equations for the large scale (slow) modes.
Journal ArticleDOI
A numerical study of three-dimensional turbulent channel flow at large Reynolds numbers
TL;DR: In this article, the three-dimensional, primitive equations of motion have been integrated numerically in time for the case of turbulent, plane Poiseuille flow at very large Reynolds numbers.
Journal ArticleDOI
On Turbulent Flow Near a Wall
TL;DR: In this paper, the authors defined the distance from wall pipe radius pipe diameter mean local velocity parallel to wall velocity fluctuations parallel and normal to flow mass density coefficient of viscosity shear stress velocity correlation coefficient mixing length universal constant in I = Ky modified universal constant eddy viscosities size of roughness friction factor = 8rw/p V 2