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Updated: Jul 23, 2026
05:20
Characterization of Thermal Transport in One-dimensional Solid Materials
Published on: January 26, 2014
Energy dissipation measures in three-dimensional disordered porous media
H Başağaoğlu1, P Meakin, S Succi
1Idaho National Laboratory, P.O. Box 1625, MS 2025, Idaho Falls, Idaho 83415, USA.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|December 31, 2005
Summary
Researchers analyzed nonlinear flow in porous media using a lattice-Boltzmann model. A new method using nonequilibrium kinetic tensors better identifies the transition to nonlinear flow in granular systems.
Area of Science:
- Fluid dynamics
- Computational physics
- Materials science
Background:
- Understanding nonlinear flow in porous media is crucial for various applications.
- Characterizing the onset of nonlinear flow in granular systems presents challenges.
- Existing methods may not fully capture the complex transitions in such systems.
Purpose of the Study:
- To analyze the onset of nonlinear flow in three-dimensional random, porous granular systems.
- To compare two quantitative methods for characterizing this transition: kinetic energy participation number and nonequilibrium kinetic tensor participation number.
- To evaluate the range of Reynolds numbers over which these transitions occur.
Main Methods:
- Utilized a lattice-Boltzmann model to simulate fluid flow.
- Employed three-dimensional random granular systems with 60% porosity.
- Calculated participation numbers based on local kinetic energies and energy dissipation rates from nonequilibrium kinetic (viscous stress) tensors.
Main Results:
- The kinetic energy participation number indicates a transition from concentrated to dispersed kinetic energy densities.
- The nonequilibrium kinetic tensor participation number shows a transition from dispersed to concentrated energy dissipation densities.
- The transition identified by the nonequilibrium kinetic tensor occurred over a similar or narrower range of Reynolds numbers.
Conclusions:
- The nonequilibrium kinetic tensor participation number provides a sensitive measure for the onset of nonlinearity in granular flows.
- This method offers a more refined characterization of flow transitions compared to kinetic energy distribution.
- The findings contribute to a better understanding of fluid behavior in porous granular media.
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