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Showing 1 to 20 of 128 for “"Large-Eddy Simulation(LES)"”.
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Numerical modelling of an oscillatory baffled column
… 6.2.16 was used to create the modeL Numerical simulations were conducted to investigate the effects of di fferent methods of defining the oscillatory flow, using both RANS turbulence models and Large Eddy Simulation (LES) to model turbulence, as well as different grid sizes and different …
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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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Entropy-stable hybridized discontinuous Galerkin methods for large-eddy simulation of transitional and turbulent flows
… reduce fuel consumption and toxic emissions. Large-eddy simulation (LES) is currently the most promising simulation technique to accurately predict transitional and turbulent flows. LES, however, remains computationally expensive and often suffers from accuracy and robustness issues to the …
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Numerical Study of Turbulent Characteristics and Aeration Patterns in Breaking Surge Waves
… caused by a sudden change in flow. 3D numerical simulation provides a holistic approach to simulate the turbulent behaviour behind a breaking surge wave. A combination of Volume of Fluid (VOF) method and Large Eddy Simulation (LES) is utilized for Froude numbers ranging from 1.71 to 2.49. …
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Numerical investigation of airflow and aerosol deposition characteristics within human airways
… of several pulmonary diseases. In this study, large-eddy simulation (LES) is used for the numerical investigation of the airflow and the aerosol deposition characteristics within the upper human airways. LES is performed using the Eulerian-Lagrangian framework where the airflow is modeled using …
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Numerical Simulation Of The Atmospheric Boundary Layer Over Complex Topography: A Modern Approach To A Classical Problem
… the atmospheric boundary layer (ABL) using large eddy simulation (LES). This framework captures the topography of the Earth’s surface rather than modeling it. To robustly simulate the ABL, four unique capabilities (temperature transport, topographic data, immersed boundary method with wall …
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Turbulence in Multiphase Models for Aeration Bubble Plumes
… of turbulence via a k - epsilon model and a Large-Eddy Simulation (LES) approach. It is based on a double averaging procedure that accounts for: (a) the presence of a two-phase flow, and (b) its turbulent nature. The model also allows for the global simulation of phenomena of break-up and …
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Study of dynamics of airflow and aerosol transport and deposition in human upper airways using large-eddy simulations
This study employs a large-eddy simulation (LES) strategy to investigate airflow and aerosol dynamics in the human upper airways using a truncated SimInhale configuration. Inflow conditions include three steady inhalation flow rates (14.2, 53.2, and 71 L/min), representing quasi-laminar, moderate, …
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Study of two-way coupled particle laden turbulent flow over a backward-facing step using large-eddy simulation
Large-eddy simulation (LES) is a computationally viable strategy to study particle-laden turbulent flows in practically relevant configurations, although modeling challenges need to be addressed for improved predictive capabilities. In this study, we perform a comprehensive assessment of …
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Experimental and Numerical Study of Air Flows in a Full Scale Room
… Navier-Stokes (RANS) method and the Large Eddy Simulation (LES) with dynamical subgrid model were evaluated with the experimental data from the VPSTV measurements. The LES provided the best predictions for the three ventilation rates while RSM predictions were closest to measurements …
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Scale adaptive turbulence modeling for in-vessel sodium thermal hydraulics
… fluid dynamics is a powerful tool for the simulation of nuclear reactor coolant flows, such as in sodium fast reactors. In these reactors, the phenomenon of thermal striping -- characterized by oscillatory turbulent mixing of non-isothermal coolant flows -- has the potential to damage the …
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Surface Curvature and Roughness Effects on Görtler Vortex Development in Hypersonic Flow
… vortices in hypersonic flow. Three-dimensional large eddy simulation (LES) was performed for two curvature cases using US3D, an unstructured-grid finite volume computational fluid dynamics (CFD) solver. Experiments were performed on two curvature cases and three roughness element shapes at the …
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Large Eddy Simulation Based Turbulent Flow-induced Vibration of Fully Developed Pipe Flow
… This thesis presents an FSI approach based on Large Eddy Simulation (LES) flow models, which do compute the instantaneous fluctuations in turbulent flow. The results based on the LES models indicate that these fluctuations contribute to the pipe vibration. It is shown that there is a near …
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Prediction of Noise Associated with an Isolated UAV Propeller
… is geared towards a world where aerial vehicles are commonplace. This poses the problem of the effects of the radiated noise. The present research presents an in-depth analysis of the noise generation mechanism of a propeller as a mode of propulsion of the said aerial vehicles. Numerical …
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Development of Eagle3D Solver For Wall Modeled LES of Transonic Flows
<p>Wall modeled Large Eddy Simulation (LES) is an area of interest due to its ability to lower computational costs of LES simulation. Even with the application of wall models, LES still proves to have practicality issues when it comes to use in industry, due to the expertise, time, and …
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Numerical studies of the wake of a plate normal to a free stream
… of a flat plate has not. At present, numerical simulations have not been reported in significant numbers and are mostly two-dimensional. The time dependent two- and three-dimensional Navier-Stokes equations are solved using the large eddy simulation (LES) technique. The two-dimensional …
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Implementation and Verification of a Synthetic Eddy Method (SEM) in the Eagle3d Compressible Flow Solver
… thesis is to implement and evaluate a Synthetic Eddy Method (SEM) into the Eagle3D compressible flow solver. Both the ability of Eagle3D to resolve unsteady turbulent ow field and capability of the SEM to reproduce given Reynolds stress profiles to start realistic turbulent behavior are verified …
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Direct Numerical Simulation of Flow Over Circular Cylinders for Large -Eddy Simulation Modeling
… using a three-dimensional direct numerical simulation (DNS). At this condition, the shear layer is unstable. However, previous direct numerical simulations of this flow have been limited to Reynolds numbers of 1000 or less, where the shear layer is stable or only weakly unstable. The …
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Study of natural ventilation in buildings with large eddy simulation
… study aims at solving these problems by using large eddy simulation (LES). In LES, a three-dimensional, time-dependent method, the contribution of the large, energy-carrying structures is computed directly and only the smallest scales of turbulence are modeled. This investigation has identified …
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On the analysis tools of turbulent and financial time series
… that simulate them e.g. the direct numerical simulation. The main models that were dealt with are the large eddy simulation (LES) and the diffusion equation which is a simplified version of the Navier-Stokes equations (NSE). Then there are tools that are used to extract different information …
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