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Fernando E. Camelli

Department of Computational and Data SciencesGeorge Mason University

E-mail: fcamelli@gmu.eduWeb:

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Atmospheric Dispersion• Study flow around buildings

• Study flow around ships

• Patterns/footprint of clouds of materials

• Tools:– CAD: Computer Aided Design– CFD: Computational Fluid Dynamics– Visualization

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FEFLO Model• Pre-Processing

– CAD FECAD– Grid generation FRGEN3D

• Solution– Flow solution FEFLO

• Post-Processing– Visualization ZFEM

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Some Examples

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Inputs for CFD Models• Topography of landscape• Building heights with footprints (locations)• Other characteristics:

– Surface roughness– Vegetative covers– Building materials

• Data are 3D in nature• Some are commonly stored in GIS

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George Mason University, Fairfax, VA

We are here

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Data• Topographic and Building

data for GMU-Fairfax campus, VA

• Original data: 5-feet contours

• Converted to raster (grid) and TIN

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Mesh from Raster Data

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Temporal – Raster• Contours of concentration @ 140 m above

sea level

10 sec 100 sec50 sec

Concentration

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Spatial – Raster• Contours of concentration @ 100 sec

135 meters 145 meters140 meters

Concentration

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Three Dimensional Cloud

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Footprint

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Concentration Profiles

1

2

3

4

Average over 180 s1 2

3 4

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New York City

→

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Building Airwake

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One Penn Plaza BuildingEmpire State Building

Concentration levels (log scale)

Velocity vectors

One Plaza BuildingEmpire State Building

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Velocity at 5 m AGL

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Comparison: WNW and SW plumes

10 seconds 400 seconds 700 seconds

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Iso-concentration

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Instantaneous Streamlines

Wind direction

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Release Location

Plume – Cut Planes

Wind direction

1.5 m above the ground

5.2 m above the ground

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Concentration Level Iso-surface

500 K 4M 31M

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LPD 17 – San Antonio Class

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Temperature Iso-Surface

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Absolute Velocity - Flow Past LPD 17

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T-AKE 1 – Dry Cargo/Ammunition Ship

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Smoke – 30 deg – Comparison

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Particles – 30 deg – No HVAC