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Showing 1 to 20 of 232 for “"Large Eddy Simulation"”.
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Toward Ideal Large -Eddy Simulation
In the second case, a coarse finite-volume representation defines the LES scales. Optimal flux models are expressed as modifications of standard fourth-order schemes, so that numerical and subgrid effects are treated simultaneously. The LES obeys only a bulk conservation of mass, but it is shown …
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Toward Ideal Large-Eddy Simulation
… is established that there is a subgrid model for large-eddy simulation (LES) of turbulence that is provably ideal in at least two important senses: a simulation using the ideal model matches all spatial statistics and minimizes error in the large-scale dynamics. However, the ideal model embodies a …
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Large Eddy Simulation Reduced Order Models
… dissertation uses spatial filtering to develop a large eddy simulation reduced order model (LES-ROM) framework for fluid flows. Proper orthogonal decomposition is utilized to extract the dominant spatial structures of the system. Within the general LES-ROM framework, two approaches are proposed to …
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Finite-Volume Optimal Large -Eddy Simulation
Finally, the dynamic optimal finite-volume LES model is applied to more a more complex flow, the temporally-growing shear layer. The results obtained with dynamic optimal finite-volume LES models are comparable with the DNS results of Rogers & Moser (1994), at a fraction of the cost. One expects …
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Large Eddy Simulation of Boundary Layer Combustion
Numerical simulations of turbulent non-premixed flames occurring in the presence of solid surfaces is a prevalent topic of interest due to the complexity of the near wall physics and the technical modeling challenges it presents. Near wall combustion phenomena is relevant in a variety of combusting …
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LARGE EDDY SIMULATION OF TURBULENT HYDROGEN FLAMES
… investigates turbulent hydrogen combustion using large eddy simulation (LES) combined with advanced combustion modeling approaches. In particular, flamelet-based models and transported probability density function (PDF) methods based on the Eulerian stochastic fields (ESF) framework are employed …
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Large eddy simulation of compressible channel flow
A large eddy simulation method for compressible channel flow simulations is developed and validated. The method separates the resolvable scale motions from the unresolvable (subgrid) scales by applying a spatial filter to the compressible Navier-Stokes equations. The Leonard and cross terms which …
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Large eddy simulation of subsonic mixing layers
Large eddy simulation is used to study the large-scale structures in a low subsonic mixing layer and their breakdown to small scales. For 3-D simulations, different finite-difference and pseudo-spectral schemes are tested. The (2, 4) MacCormack Scheme developed by Gottlieb and Turkel (1976) shows …
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Optimal Large -Eddy Simulation of Turbulent Channel Flow
… computed from realizations of a direct numerical simulation (DNS) of a plane channel at a friction Reynolds number of 587. Due to the limited number of realizations, estimates of the model term are global only in the streamwise and spanwise directions and local in the wall-normal direction. …
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Large eddy simulation of primary liquid-sheet breakup
… in this thesis. To be readily applicable to the simulation of atomisation, the novel interfacecapturing technique has been embedded in a framework — within the open source CFD code OpenFOAM — that solves the velocity and pressure fields, outputs droplet characteristics and runs in parallel. In …
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Large eddy simulation of premixed combustion using flamelets
Large Eddy Simulation (LES) has potential to address unsteady phenomena in turbulent premixed flames and to capture turbulence scales and their influence on combustion. Thus, this approach is gaining interest in industry to analyse turbulent reacting flows. In LES, the dynamics of large-scale …
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Large eddy simulation of the upper atmospheric surface layer
… conditions. A numerical tool, three-dimensional large eddy simulation (LES), is adopted to simulate turbulence in the ABL, with a fine resolution in the ASL, so that an "a priori value” of the von }Carman constant and the Monin-Obukhov similarity formulas can be derived from the resolved-scale …
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LARGE-EDDY SIMULATION OF DEEP-WATER HYDROCARBON PLUME DYNAMICS
… hydration effects into a fast Eulerian-Eulerian large-eddy simulation (LES) model. By simultaneously simulating the evolutions of the bubble mass concentration and number density functions, the average bubble size in each LES computational cell can be calculated locally. Based on the …
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Towards Optimal Large-Eddy Simulation of Wall-Bounded Flows
… the wall is addressed via a review of the OLES simulation of turbulent channel flow performed by Das (2004). In this approach, a buffer region with zero velocity is attached adjacent to the wall, and the extended velocity field is filtered using a Fourier-cutoff filter in all directions. The …
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Large eddy simulation of turbulent vortices and mixing layers
In this dissertation large-eddy simulation(LES) is used to study the transitional and turbulent structures of vortices and free shear layers. The recently developed dynamic model and the basic Smagorinsky model are utilized to model the subgrid-scale(SGS) stress tensor. The dynamic model has many …
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Large -eddy simulation of a three-dimensional compressible tornado vortex
Large-Eddy simulation (LES) has become a very useful tool for investigating tornadoes, one of the more spectacular and destructive phenomena of nature. A new three-dimensional, unsteady, compressible model is generated to determine how significant the differences between compressible and …
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