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Magnetic excitation of a granular gas as a bulk thermostat.

ABSTRACT: A thermostat utilizing a varying magnetic field has been developed to agitate soft ferromagnetic particles in microgravity platforms for an investigation of an energy-dissipative granular gas. Although the method has experimentally realized a reasonably homogeneous spatial distribution of particles, the physics behind the magnetically excited particles has not been understood. Therefore, a numerical calculation based on the discrete element method is developed in this paper to explain the realization of homogeneously distributed particles. The calculation method allows considering inelastic and magnetic interactions between particles and tracking the motions due to those interactions during the excitation of the granular gas. The calculation results, compared with the experimental result, show that magnetic interactions between particles, a time-domain variation of magnetic-excitation directions, and random collisions of particles between each magnetic excitation contribute to distribute particles homogeneously.

SUBMITTER: Adachi M

PROVIDER: S-EPMC6692374 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Magnetic excitation of a granular gas as a bulk thermostat.

Adachi Masato M Yu Peidong P Sperl Matthias M

NPJ microgravity 20190813

A thermostat utilizing a varying magnetic field has been developed to agitate soft ferromagnetic particles in microgravity platforms for an investigation of an energy-dissipative granular gas. Although the method has experimentally realized a reasonably homogeneous spatial distribution of particles, the physics behind the magnetically excited particles has not been understood. Therefore, a numerical calculation based on the discrete element method is developed in this paper to explain the realiz ...[more]

PMID: 31428675

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