Searched for: subject:"large%5C+eddy%5C+simulation"
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Mehta, D. (author), Zhang, Y. (author), van Zuijlen, A.H. (author), Bijl, H. (author)
Despite advances in turbulence modelling, the Smagorinsky model remains a popular choice for large eddy simulation (LES) due to its simplicity and ease of use. The dissipation in turbulence energy that the model introduces, is proportional to the Smagorinsky constant, of which many different values have been proposed. These values have been...
journal article 2019
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van der Linden, S.J.A. (author), Edwards, John M. (author), van Heerwaarden, Chiel C. (author), Vignon, Etienne (author), Genthon, Christophe (author), Petenko, Igor (author), Baas, P. (author), Jonker, H.J.J. (author), van de Wiel, B.J.H. (author)
Observations of two typical contrasting weakly stable and very stable boundary layers from the winter at Dome C station, Antarctica, are used as a benchmark for two centimetre-scale-resolution large-eddy simulations. By taking the Antarctic winter, the effects of the diurnal cycle are eliminated, enabling the study of the long-lived steady...
journal article 2019
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van Hooft, J.A. (author), Popinet, Stéphane (author), van Heerwaarden, Chiel C. (author), van der Linden, S.J.A. (author), de Roode, S.R. (author), van de Wiel, B.J.H. (author)
We present a proof-of-concept for the adaptive mesh refinement method applied to atmospheric boundary-layer simulations. Such a method may form an attractive alternative to static grids for studies on atmospheric flows that have a high degree of scale separation in space and/or time. Examples include the diurnal cycle and a convective...
journal article 2018
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Benard, P. (author), Viré, A.C. (author), Moureau, V. (author), Lartigue, G. (author), Beaudet, L. (author), Deglaire, P (author), Bricteux, L (author)
Accurate simulation of wind turbine wakes is critical for the optimization of turbine efficiency and prediction of fatigue loads. These wakes are three-dimensional, complex, unsteady and can evolve in geometrically complex environments. Modeling these flows calls thus for high-quality numerical methods that are able to capture and transport thin...
journal article 2018
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Eisma, H.E. (author), Tomas, J.M. (author), Pourquie, M.J.B.M. (author), Elsinga, G.E. (author), Jonker, H.J.J. (author), Westerweel, J. (author)
Simultaneous particle-image velocimetry and laser-induced fluorescence combined with large-eddy simulations are used to investigate the flow and pollutant dispersion behaviour in a rural-to-urban roughness transition. The urban roughness is characterized by an array of cubical obstacles in an aligned arrangement. A plane fence is added one...
journal article 2018
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Matheis, Jan (author), Hickel, S. (author)
We present and evaluate a two-phase model for Eulerian large-eddy simulations (LES) of liquid-fuel injection and mixing at high pressure. The model is based on cubic equations of state and vapor-liquid equilibrium calculations and can represent the coexistence of supercritical states and multi-component subcritical two-phase states via a...
journal article 2018
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Boersma, S. (author), Rostampour Samarin, Vahab (author), Doekemeijer, B.M. (author), van Wingerden, J.W. (author), Keviczky, T. (author)
In this paper, we present an implementation of a model predictive controller (MPC) for wind farm power tracking problem. The controller is evaluated in the high-fidelity PAral-lelized Large-eddy simulation Model (PALM). By taking measurements from PALM, we show that the closed-loop MPC can provide power reference tracking while reducing force...
journal article 2018
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Neggers, R.A.J. (author), Ackerman, Andrew S. (author), Angevine, W. M. (author), Bazile, Eric (author), Beau, I. (author), Blossey, P. N. (author), Boutle, I. A. (author), de Bruijn, C. (author), cheng, A (author), van der Dussen, J.J. (author), Fletcher, J. (author), Dal Gesso, S (author), Jam, A. (author), Kawai, H (author), Cheedela, S. K. (author), Larson, V. E. (author), Lefebvre, Marie Pierre (author), Lock, A. P. (author), Meyer, N. R. (author), de Roode, S.R. (author), de Rooy, WC (author), Sandu, I (author), Xiao, H (author), Xu, K. M. (author)
Results are presented of the GASS/EUCLIPSE single-column model intercomparison study on the subtropical marine low-level cloud transition. A central goal is to establish the performance of state-of-the-art boundary-layer schemes for weather and climate models for this cloud regime, using large-eddy simulations of the same scenes as a...
journal article 2017
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Yang, Y. (author), Veldhuis, L.L.M. (author), Eitelberg, G. (author)
Abstract: During the ground operation of aircraft, the interaction between the propulsor-induced flow field and the ground may lead to the generation of ground vortices. Utilizing numerical approaches, the source of vorticity entering ground vortices is investigated. The results show that the production of wall-parallel components of...
journal article 2017
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Tomas, J.M. (author), Eisma, H.E. (author), Pourquie, M.J.B.M. (author), Elsinga, G.E. (author), Jonker, H.J.J. (author), Westerweel, J. (author)
Both large-eddy simulations (LES) and water-tunnel experiments, using simultaneous stereoscopic particle image velocimetry and laser-induced fluorescence, have been used to investigate pollutant dispersion mechanisms in regions where the surface changes from rural to urban roughness. The urban roughness was characterized by an array of...
journal article 2017
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Ma, L. (author), Huang, X. (author), Roekaerts, D.J.E.M. (author)
We report results of a computational study of oxy-fuel spray jet flames. An experimental database on flames of ethanol burning in a coflow of a O2–CO2 mixture, created at CORIA (Rouen, France), is used for model validation (Cléon et al., 2015). Depending on the coflow composition and velocity the flames in these experiments start at nozzle (type...
journal article 2017
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Basu, S. (author), Lacser, Avraham (author)
In several recent large-eddy simulation studies, the lowest grid level was located well within the roughness sublayer. Monin–Obukhov similarity-based boundary conditions cannot be used under this scenario, and in this note we elaborate on this fundamental problem and suggest potential solutions.
journal article 2017
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Mehta, D. (author)
This thesis concerns the industrial application of large eddy simulation to wind farm aerodynamics. Through a series of simple tests, it presents the pros and cons of using energy-conserving time integration and furthers the importance of a dissipation-free spatial discretisation. Finally, it demonstrates the capability of the Energy-Conserving...
doctoral thesis 2016
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Schalkwijk, J. (author), Jonker, H.J.J. (author), Siebesma, A.P. (author)
The low-frequency contribution to the systematic and random sampling errors in single-tower eddy-covariance flux measurements is investigated using large-eddy simulation (LES). We use a continuous LES integration that covers a full year of realistic weather conditions over Cabauw, the Netherlands, and emulate eddy-covariance measurements. We...
journal article 2016
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Tomas, J.M. (author), Pourquie, M.J.B.M. (author), Jonker, H.J.J. (author)
Large-eddy simulations (LES) are used to investigate the effect of stable stratification on rural-to-urban roughness transitions. Smooth-wall turbulent boundary layers are subjected to a generic urban roughness consisting of cubes in an in-line arrangement. Two line sources of pollutant are added to investigate the effect on pollutant dispersion...
journal article 2016
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Righolt, B.W. (author), Kenjeres, S. (author), Kalter, R. (author), Tummers, M.J. (author), Kleijn, C.R. (author)
We demonstrate how the self-sustained oscillation of a confined jet in a thin cavity can be quantitatively described by a zero-dimensional model of the delay differential equation type with two a priori predicted model constants. This model describes the three phases in self-sustained oscillations: (i) pressure driven growth of the oscillation, ...
journal article 2015
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We propose a new definition of the length scale in an eddy-viscosity model for large-eddy simulations (LES). This formulation extends and generalizes a previous proposal [Piomelli, Rouhi and Geurts, Proc. ETMM10, 2014], in which the LES length scale was expressed in terms of the integral length-scale of turbulence determined by the flow...
conference paper 2015
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Örley, F. (author), Trummler, T. (author), Hickel, S. (author), Mihatsch, M.S. (author), Schmidt, S.J. (author), Adams, N.A. (author)
We employ a barotropic two-phase/two-fluid model to study the primary break-up of cavitating liquid jets emanating from a rectangular nozzle, which resembles a high aspect-ratio slot flow. All components (i.e., gas, liquid, and vapor) are represented by a homogeneous mixture approach. The cavitating fluid model is based on a thermodynamic...
journal article 2015
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Schalkwijk, J. (author)
De vorige eeuw was getuige van de opkomst van numerieke weer- en klimaatmodellen. Weersvoorspelling, voorheen een empirische procedure gebaseerd op de persoonlijke ervaring van de meteoroloog, ontwikkelde zich tot een wetenschappelijke methode om de toekomstige toestand van de atmosfeer te voorspellen op basis van de huidige toestand en tendens....
doctoral thesis 2015
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Schalkwijk, J. (author), Jonker, H.J.J. (author), Siebesma, A.P. (author), Bosveld, F.C. (author)
Results are presented of two large-eddy simulation (LES) runs of the entire year 2012 centered at the Cabauw observational supersite in the Netherlands. The LES is coupled to a regional weather model that provides the large-scale information. The simulations provide three-dimensional continuous time series of LES-generated turbulence and clouds,...
journal article 2015
Searched for: subject:"large%5C+eddy%5C+simulation"
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