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Zero-gravity thermal convection in granular gases
A Rodríguez-Rivas1, M A López-Castaño1, F Vega Reyes1
1Departamento de Física and Instituto de Computación Científica Avanzada (ICCAEx), Universidad de Extremadura, 06006 Badajoz, Spain.
Physical Review. E
|August 16, 2020
Summary
This study reveals gravity-free thermal convection in granular gases, driven by internal gradients, not external heat. This phenomenon occurs without typical Rayleigh-Bénard conditions.
Area of Science:
- Physics
- Granular Materials Science
Background:
- Convective flow in granular fluids typically requires gravity and thermal gradients (Rayleigh-Bénard convection).
- Previous studies focused on external forces driving convection in granular systems.
Purpose of the Study:
- To investigate the possibility of thermal convection in granular gases without gravity or external thermal gradients.
- To identify the driving mechanisms for convection under novel conditions.
Main Methods:
- Utilized an event-driven algorithm for simulating inelastic hard disks.
- Modeled a granular gas composed of identical disks within a rectangular region.
Main Results:
- Demonstrated evidence of steady, gravity-free thermal convection in the granular gas.
- Showed that internal gradients arising from dissipation and thermal sources at uniform temperature can sustain convection.
Conclusions:
- Thermal convection can occur in granular gases independent of gravity and external thermal gradients.
- Internal energy dissipation and uniform temperature sources are sufficient to drive convection in these systems.
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