Publication

Counter-Gradient, Co-Gradient and ‘Surface-Layer' Momentum Fluxes in Nocturnal Slope Flows over Steep Alpine Terrain

Related publications (39)

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The wind-driven redistribution of snow has a significant impact on the climate and mass balance of polar and mountainous regions. Locally, it shapes the snow surface, producing dunes and sastrugi. Sediment transport has been mainly represented as a functio ...
Amer Geophysical Union2016

Wake flow in a wind farm during a diurnal cycle

Fernando Porté Agel, Mahdi Abkar, Ahmad Sharifi

The atmospheric boundary layer (ABL) undergoes substantial changes in its structure and dynamics in the course of a day due to the transient nature of forcing factors such as the surface fluxes of heat and momentum. The non-stationary nature of the mean wi ...
Taylor & Francis2016

Buoyant Turbulent Kinetic Energy Production in Steep-Slope Katabatic Flow

Marc Parlange, Chad Higgins, Holly Jayne Oldroyd, Eric Richard Pardyjak

We develop several critical concepts that should be considered when interpreting, modelling and designing future experiments for flows over sloping terrain. Vertical buoyancy fluxes in katabatic flows can be positive and a source of turbulent kinetic energ ...
Springer Verlag2016

Stable Atmospheric Boundary-Layer Flows over a Steep, Alpine Slope: Observations, Theory and Multi-Scale Transport Dynamics

Marc Parlange, Chad Higgins, Holly Jayne Oldroyd, Eric Richard Pardyjak

Katabatic flows are high density air flows traversing down a slope under the action of a gravitational force. These flows can be exploited for wind energy and are gaining importance in predicting scalar transport (e.g. pollutants, water vapor, CO2 drainage ...
2015

Turbulent Transport in Complex, Alpine Environments

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Turbulent exchanges between the atmosphere and the underlying surface transport heat, moisture, momentum and pollutants, and thus understanding them is crucial to water resource management, meteorological predictions, climate modeling, wind energy producti ...
EPFL2015

Atmospheric Flow Development and Associated Changes in Turbulent Sensible Heat Flux over a Patchy Mountain Snow Cover

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In this study, the small-scale boundary layer dynamics and the energy balance over a fractional snow cover are numerically investigated. The atmospheric boundary layer flows over a patchy snow cover were calculated with an atmospheric model (Advanced Regio ...
Amer Meteorological Soc2015

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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 ...
2015

Influence of atmospheric stability on wind-turbine wakes: A large-eddy simulation study

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In this study, large-eddy simulation is combined with a turbine model to investigate the influence of atmospheric thermal stability on wind-turbine wakes. The simulation results show that atmospheric stability has a significant effect on the spatial distri ...
American Institute of Physics2015

Buoyant turbulence kinetic energy (TKE) production in katabatic flow despite stable thermal stratification

Marc Parlange, Chad Higgins, Holly Jayne Oldroyd, Eric Richard Pardyjak

As micrometeorological research shifts to increasingly non-idealized environments, the lens through which we view classical atmospheric boundary layer theory must also shift to accommodate unfamiliar behavior. We present observations of katabatic flow over ...
2015

Momentum balance of katabatic flow on steep slopes covered with short vegetation

Marc Parlange, Gabriel George Katul, Holly Jayne Oldroyd, Eric Richard Pardyjak

Katabatic flows over alpine mountainous terrain differ from their forested or bare slope counterparts due to the presence of well-ventilated, short vegetation. The impact of a grass canopy and larger-scale pressure perturbations on the one-dimensional mean ...
American Geophysical Union2014

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