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Continuum model for steady, fully developed saltation above a horizontal particle bed
J T Jenkins1, I Cantat, A Valance
1Department of Theoretical and Applied Mechanics, Cornell University, Ithaca, New York 14853, USA.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|September 28, 2010
Summary
We developed a new continuum model for granular saltation, offering analytical solutions for particle pressure and shear stress. This model accurately predicts particle and wind velocity profiles, validated by wind tunnel experiments.
Area of Science:
- Geophysics
- Fluid Dynamics
- Granular Physics
Background:
- Saltation is a key aeolian process involving particle movement.
- Existing discrete numerical simulations are computationally intensive.
- Analytical models are needed for broader applications.
Purpose of the Study:
- To develop a continuum model for steady, fully developed saltation.
- To derive analytical expressions for particle pressure and shear stress.
- To extend the model for nonuniform and unsteady saltation scenarios.
Main Methods:
- Developed a continuum model for granular saltation.
- Derived local, analytical expressions for particle pressure and shear stress.
- Predicted concentration, particle velocity, and wind velocity fields.
Main Results:
- The model provides analytical solutions, contrasting with discrete simulations.
- Predicted profiles for concentration, particle, and wind velocity show good agreement with experimental data.
- The continuum approach offers advantages for extending to complex situations.
Conclusions:
- The proposed continuum model effectively describes steady saltation.
- Analytical predictions align well with wind tunnel experimental results.
- The model's extensibility facilitates analysis of more complex granular flow dynamics.
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