Monitoring Unresolved Scales in Multiscale Turbulence Modeling
نویسندگان
چکیده
This paper extends the two-level Variational MultiScale (VMS) method for Large-Eddy Simulation, introduced by Hughes et al. [Comput. Visual. Sci., 3:47–59 (2000)], to a threelevel approach that clarifies the role of unresolved scales of motion on the resolved scales. It is shown that the multi-scale framework does not obviate modeling on the large-scales, but that VMS allows for different modeling assumptions to be used on each scale range. In particular, one can choose to neglect the effect of the unresolved scales on the large scales which is reasonable for sufficiently large scale separation.
منابع مشابه
Ensemble Kalman filters for dynamical systems with unresolved turbulence
Ensemble Kalman filters are developed for turbulent dynamical systems where the forecast model does not resolve all the active scales of motion. These filters are based on the assumption that a coarse-resolution model is intended to predict the large-scale part of the true dynamics; since observations invariably include contributions from both the resolved large scales and the unresolved small ...
متن کاملStochastic Superparameterization and Multiscale Filtering of Turbulent Tracers
Data assimilation or filtering combines a numerical forecast model and observations to provide accurate statistical estimation of the state of interest. In this paper we are concerned with accurate data assimilation of a sparsely observed passive tracer advected in turbulent flows using a reduced-order forecast model. The turbulent flows which contain anisotropic and inhomogeneous structures su...
متن کاملVariational Multiscale Residual-driven Turbulence Modeling for Large Eddy Simulation of Incompressible Flow
The objectives of recent variational multiscale work in turbulence have been to capture all scales consistently and to avoid use of eddy viscosities altogether. This holds the promise of more accurate and efficient LES procedures. In this work, we describe a new variational multiscale formulation, which makes considerable progress toward these goals.
متن کاملLecture 4: The Navier-Stokes Equations: Turbulence
1 Goal In this Lecture, we shall present the main ideas behind the simulation of fluid turbulence. We firts discuss the case of the direct numerical simulation, in which all scales of motion within the grid resolution are simulated and then move on to turbulence modeling, where the effect of unresolved scales on the resolved ones is taken into account by various forms of modeling, 1
متن کاملN ov 2 00 8 Stochastic Modeling of Unresolved Scales in Complex Systems ∗
Model uncertainties or simulation uncertainties occur in mathematical modeling of multiscale complex systems, since some mechanisms or scales are not represented (i.e., “unresolved”) due to lack in our understanding of these mechanisms or limitations in computational power. The impact of these unresolved scales on the resolved scales needs to be parameterized or taken into account. A stochastic...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2000