Experimental study on the kinetics of granular gases under microgravity
説明
<jats:p>The kinetics of granular gases, including both freely cooling and steadily driven systems, is studied experimentally in quasi-two-dimensional cells. Under microgravity conditions achieved inside an aircraft flying parabolic trajectories, the frictional force is reduced. In both the freely cooling and steadily driven systems, we confirm that the velocity distribution function has the form exp(−α|<jats:italic>v</jats:italic>|<jats:sup>β</jats:sup>). The value of exponent β is close to 1.5 for the driven system in a highly excited case, which is consistent with theory derived under the assumption of the existence of the white-noise thermostat (van Noije & Ernst, <jats:italic>Gran. Mat</jats:italic>., vol. 1, 1998, p. 5764). In the freely cooling system, the value of β evolves from 1.5 to 1 as the cooling proceeds, and the system's energy decays algebraically (<jats:italic>T</jats:italic><jats:sub><jats:italic>g</jats:italic></jats:sub> = <jats:italic>T</jats:italic><jats:sub>0</jats:sub>(1 + <jats:italic>t</jats:italic>/τ)<jats:sup>−2</jats:sup>), agreeing with Haff's law (Haff, <jats:italic>J. Fluid Mech</jats:italic>., vol. 134, 1983, p. 401430).</jats:p>
収録刊行物
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- Journal of Fluid Mechanics
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Journal of Fluid Mechanics 641 521-539, 2009-12-10
Cambridge University Press (CUP)
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詳細情報 詳細情報について
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- CRID
- 1360285708009793152
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- ISSN
- 14697645
- 00221120
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- データソース種別
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- Crossref
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