A Comparative Numerical Study Of Dust Devils

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A Comparative Numerical Study Of Dust Devils
L. Prieto and C. F. Lange Department of
Mechanical Engineering University of Alberta,
Edmonton, Alberta, Canada

• Establish a simple method to compare several
  laboratory models.
• The need for comparing quantitative values in
  different environments laboratory, Earth, Mars,
  and

Open Model
Wards Model
Natures Model
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• Numerical Models

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• Dust Devils Regions

• The Corner Region, the turning point

The outer boundary is defined at r0, where the
maximum radial inward velocity is located.
Radial profiles of radial velocity component
Wards Model
Open Model
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• Dust Devils Regions, Cont.

2. The Inflow Region, the inflow zone
The top boundary is defined at h, where the
maximum axial velocity is located.
Vertical profiles of axial velocity component
Open Model
Wards Model
More
Acknowledgments U of A/FGSR, GSA, CSA, U of
A/Dept. of Mech. Eng.
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• Ideal Vortex

Wards Model
Ideal profile for tangential velocity component
in a vortex
Open Model
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• Numerical Modelling Validation

Vertical profiles of radial velocity component
Wards Model, Lund and Snow, 1993
Wards Model Simulation
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• Numerical Modelling Validation, Cont.

Vertical profiles of tangential velocity component
Wards Model, Lund and Snow, 1993
Wards Model Simulation
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• Numerical Modelling Validation, Cont.

Vertical profiles of axial velocity component
Wards Model, Lund and Snow, 1993
Wards Model Simulation
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• Dust Devil Schematic

Schematic of velocity vector contours
Wards Model
Open Model
End