Concept

Wind speed

Publications associées (311)

Estimation of wet surface evaporation from sensible heat flux measurements

A new method is proposed to estimate wet surface evaporation by means of measurements of sensible heat flux and of air temperature, relative humidity, and wind speed at one level only. This formulation is made possible by the linearization of the Bowen rat ...

American Geophysical Union2009

Large-Eddy Simulation of the Convective Atmospheric Boundary Layer over Heterogeneous Land Surfaces

Marc Parlange, Chad Higgins, Eric Richard Pardyjak, Daniel Nadeau

The parameterization of the atmospheric boundary layer is essential for accurate numerical weather predictions. The near-surface values of air temperature or wind speed for instance are highly dependent on the complex land – atmosphere interactions over he ...

2009

Surface Heterogeneity Effects on Regional-Scale Fluxes in Stable Boundary Layers: Surface Temperature Transitions

Fernando Porté Agel

Large-eddy simulation, with recently developed dynamic subgrid-scale models, is used to study the effect of heterogeneous surface temperature distributions on regional-scale turbulent fluxes in the stable boundary layer (SBL). Simulations are performed of ...

2009

On the link between ocean biota emissions, aerosol, and maritime clouds: Airborne, ground, and satellite measurements off the coast of California

Athanasios Nenes

Surface, airborne, and satellite measurements over the eastern Pacific Ocean off the coast of California during the period between 2005 and 2007 are used to explore the relationship between ocean chlorophyll a, aerosol, and marine clouds. Periods of enhanc ...

2009

The Effects of Building Representation and Clustering in Large-Eddy Simulations of Flows in Urban Canopies

Marc Parlange, Jan Overney

We perform large-eddy simulations of neutral atmospheric boundary-layer flow over a cluster of buildings surrounded by relatively flat terrain. The first investigated question is the effect of the level of building detail that can be included in the numeri ...

2009

Experimental investigation on the aerodynamic loads and wake flow features of low aspect-ratio triangular prisms at different wind directions

Giacomo Valerio Iungo

The results are described of measurements of the mean and fluctuating forces acting on low aspect-ratio triangular prisms placed vertically on a plane, having isosceles triangular cross-section with 60∘ or 90∘ apex angles and aspect ratios ranging from 1.0 ...

Elsevier2009

Velocity and Surface Shear Stress Distributions Behind a Rough-to-Smooth Surface Transition: A Simple New Model

Fernando Porté Agel

A simple new model is proposed to predict the distribution of wind velocity and surface shear stress downwind of a rough-to-smooth surface transition. The wind velocity is estimated as a weighted average between two limiting logarithmic profiles: the first ...

2009

Localizing an Odor Source and Avoiding Obstacles: Experiments in a Wind Tunnel using Real Robots

Alcherio Martinoli, Thomas Lochmatter, Nicolas Heiniger

We report on real-robot odor source localization experiments carried out in an environment with obstacles in the odor plume. The robot was equipped with an ethanol sensor and a wind direction sensor, and the experiments were carried out in a wind tunnel, i ...

2009

Determination of the Thermal Roughness Length for a Built Environment

Martin Vetterli, Marc Parlange, Guillermo Barrenetxea Kobas, Daniel Nadeau

In this study, the scalar roughness for sensible heat in the temperature profile (z0,h) is determined based on direct skin temperature measurements and profiles of wind and temperature in a complex urban environment. Typically, skin temperatures are inferr ...

2008

A pilot study on the pollen representation of mountain valley vegetation in the central Alps

Jed Oliver Kaplan

The relative pollen productivity (RPP) of Pinus cembra, Larix, Picea, Gramineae, and Cyperaceae was estimated for the Upper Engadine area, an inner-alpine sub-continental valley in SE Switzerland lying above 1800 m a.s.l. The influx of pollen originating f ...

2008

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