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Integration through transients approach to the μ(I) rheology
O Coquand1, M Sperl1,2, W T Kranz1,2
1Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 51170 Köln, Germany.
Physical Review. E
|October 20, 2020
Summary
This study extends a granular flow method to calculate pressure, supporting empirical rheology laws and confirming friction
Area of Science:
- Physics
- Mechanical Engineering
Background:
- Granular flow is crucial in various industrial processes.
- Existing models for granular flow, like empirical μ(I) rheology laws, have practical success but lack comprehensive theoretical underpinnings.
Purpose of the Study:
- To generalize the granular integration through transients (GIT) formalism for pressure determination in granular flows.
- To provide theoretical support for the widely used μ(I) rheology laws.
- To investigate the role of interparticle friction in the Bagnold regime.
Main Methods:
- Extension of the granular integration through transients (GIT) formalism.
- Analysis of granular flows within the Bagnold regime.
- Theoretical validation of empirical rheology laws.
Main Results:
- The GIT formalism is successfully generalized for pressure calculations in granular flows.
- Theoretical support is provided for empirical μ(I) rheology laws.
- It is confirmed that interparticle friction is negligible in the Bagnold regime where μ(I) laws are applicable.
Conclusions:
- The generalized GIT formalism offers a robust theoretical framework for analyzing granular flow pressure.
- The findings validate the applicability and theoretical basis of μ(I) rheology laws in specific granular flow conditions.
- The irrelevance of interparticle friction in the Bagnold regime simplifies granular flow modeling.
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