Numerical analysis of the nonlinear subgrid scale method

نویسندگان

  • I. P. SANTOS
  • R. C. ALMEIDA
چکیده

This paper presents the numerical analysis of the Nonlinear Subgrid Scale (NSGS) model for approximating singularly perturbed transport models. The NSGS is a free parameter subgrid stabilizing method that introduces an extra stability only onto the subgrid scales. This new feature comes from the local control yielded by decomposing the velocity field into the resolved and unresolved scales. Such decomposition is determined by requiring the minimum of the kinetic energy associated to the unresolved scales and the satisfaction of the resolved scale model problem at element level. The developed method is robust for a wide scope of singularly perturbed problems. Here, we establish the existence and uniqueness of the solution, and provide an a priori error estimate. Convergence tests on two-dimensional examples are reported. Mathematical subject classification: Primary: 65N12; Secondary: 74S05.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

A Generalized Convection-Diffusion Model for Subgrid Transport in Porous Media

Models for transport in heterogeneous subsurface formations usually require some type of treatment for subgrid effects. In this work, a generalized nonlinear convection-diffusion model for subgrid transport in two-dimensional systems is developed and applied. The model, although somewhat heuristic, is motivated by previous findings within both the stochastic and the deterministic frameworks. Th...

متن کامل

A stochastic extension of the explicit algebraic subgrid-scale models

Articles you may be interested in Multifractal subgrid-scale modeling within a variational multiscale method for large-eddy simulation of passive-scalar mixing in turbulent flow at low and high Schmidt numbers The physics of energy transfer toward improved subgrid-scale models A hybrid subgrid-scale model constrained by Reynolds stress A dynamic subgrid-scale eddy viscosity model with a global ...

متن کامل

Fast Numerical simulations of 2D turbulence using a dynamic model for Subgrid Motions

We present numerical simulation of 2D turbulent flow using a new model for the subgrid scales which are computed using a dynamic equation linking the subgrid scales with the resolved velocity. This equation is not postulated, but derived from the constitutive equations under the assumption that the non-linear interactions of subgrid scales between themselves are equivalent to a turbulent viscos...

متن کامل

Numerical modeling of subgrid heterogeneity in two phase flow simulations

[1] A coarse-scale model governing two-phase viscous dominated flow in heterogeneous porous media is presented. The coarse-scale water transport equation (or saturation equation) is derived from a volume average of the underlying fine-scale saturation equation. A key component of the coarse-scale description is the subgrid model, which appears in the formulation as a nonlinear, nonlocal term in...

متن کامل

Analysis of a Two-Scale, Locally Conservative Subgrid Upscaling for Elliptic Problems

We present a two-scale theoretical framework for approximating the solution of a second order elliptic problem. The elliptic coefficient is assumed to vary on a scale that can be resolved on a fine numerical grid, but limits on computational power require that computations be performed on a coarse grid. We consider the elliptic problem in mixed variational form over W × V ⊂ L2 × H(div). We base...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2012