Publication
A Modulated-Gradient Parametrization for the Large-Eddy Simulation of the Atmospheric Boundary Layer Using the Weather Research and Forecasting Model
Publications associées (40)
Flow and Snow in Complex Terrain: across-scale modelling for a correct surface mass balance
Varun Sharma, Michael Lehning, Wolf Hendrik Huwald, Jérôme François Sylvain Dujardin, Franziska Gerber, Daniela Brito Melo, Nander Wever, Armin Sigmund, David Nicholas Wagner
Preferential deposition of snow precipitation, snow transport and snow sublimation modify the mass which gets incorporated into or removed from the seasonal or perennial snow cover. These processes happen at very small scales from snow grain size to larger ...
2023On the Capability of Wall-Modeled Large Eddy Simulations to Predict Particle Dispersion in Complex Turbulent Flows
Mohamed Aly Hashem Mohamed Sayed
Predicting particle transport in turbulent flows has a plethora of applications, some of which are: the transport of atmospheric aerosols, the deposition of blood cells in the arteries of human bodies and the atomization of fuel droplets in combustion cham ...
EPFL2022A physics-based model for wind turbine wake expansion in the atmospheric boundary layer
Fernando Porté Agel, Dara Vahidi
Analytical wind turbine wake models are widely used to predict the wake velocity deficit. In these models, the wake growth rate is a key parameter specified mainly with empirical formulations. In this study, a new physics-based model is proposed and valida ...
2022REMA topography and AntarcticaLC2000 for WRF
Michael Lehning, Franziska Gerber
Reference Elevation Model of Antarctica (REMA) topography and AntarcticaLC2000 landuse dataare now available as static data input for the Weather Research and Forecasting model (WRF). Topographyand landuse are made available at a spatial resolution of 1 km ...
2020Katabatic Flow: A Closed-Form Solution with Spatially-Varying Eddy Diffusivities
Jiannong Fang, Peter Monkewitz, Marc Parlange, Marco Giovanni Giometto
The Nieuwstadt closed-form solution for the stationary Ekman layer is generalized for katabatic flows within the conceptual framework of the Prandtl model. The proposed solution is valid for spatially-varying eddy viscosity and diffusivity (O'Brien type) a ...
Springer Verlag2017Theoretical and numerical studies of atmospheric boundary-layer flows over complex terrain
Atmospheric boundary-layer (ABL) flows over complex terrain have been the focus of active research, given their impact on weather and climate variability. Surface complexity is understood in a broad sense and includes variation in roughness properties, inc ...
EPFL2016Large-eddy simulation of atmospheric boundary layer flow and passive scalar dispersion over idealized urban surfaces
Fernando Porté Agel, Wai Chi Cheng
Accurate prediction of atmospheric boundary layer (ABL) flow and its interaction with urban surfaces is critical for understanding the transport of momentum and scalars within and above cities. This, in turn, is essential for predicting the local climate a ...
2015Development of a new 1D urban canopy model: coherences between surface parameterizations
Dasaraden Mauree, Alain Clappier
A 1-D Canopy Interface Model (CIM) was developed in order to better simulate the effect of urban obstacles on the atmosphere in the boundary layer. The model solves the Navier-Stokes equations on a high-resolved gridded vertical column. The effect of the s ...
2015Large-eddy simulation of very-large-scale motions in atmospheric boundary-layer flows
Fernando Porté Agel, Jiannong Fang
In the last few decades, laboratory experiments and direct numerical simulations of turbulent boundary layers, performed at low to moderate Reynolds numbers, have found very-large-scale motions (VLSMs) in the logarithmic and outer regions. The size of VLSM ...
2015Large-Reynolds-number asymptotics of the streamwise normal stress in zero-pressure-gradient turbulent boundary layers
A more poetic long title could be 'A voyage from the shifting grounds of existing data on zero-pressure-gradient (abbreviated ZPG) turbulent boundary layers (abbreviated TBLs) to infinite Reynolds number'. Aided by the requirement of consistency with the R ...
Cambridge University Press2015