Granular cooling of ellipsoidal particles in microgravity.

Autor: Pitikaris S; Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 51170, Köln, Germany., Bartz P; Institut für Theoretische Physik, Universität zu Köln, 50937, Köln, Germany., Yu P; Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 51170, Köln, Germany. peidong.yu@dlr.de.; Institut für Theoretische Physik, Universität zu Köln, 50937, Köln, Germany. peidong.yu@dlr.de., Cristoforetti S; European Astronaut Centre, 51147, Köln, Germany., Sperl M; Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 51170, Köln, Germany.; Institut für Theoretische Physik, Universität zu Köln, 50937, Köln, Germany.
Jazyk: angličtina
Zdroj: NPJ microgravity [NPJ Microgravity] 2022 Apr 20; Vol. 8 (1), pp. 11. Date of Electronic Publication: 2022 Apr 20.
DOI: 10.1038/s41526-022-00196-6
Abstrakt: A three-dimensional granular gas of ellipsoids is established by exposing the system to the microgravity environment of the International Space Station. We use two methods to measure the dynamics of the constituent particles and report the long-time development of the granular temperature until no further particle movement is detectable. The resulting cooling behavior can be well described by Haff's cooling law with time scale τ. Different analysis methods show evidence of particle clustering towards the end of the experiment. By using the kinetic theory for ellipsoids we compare the translational energy dissipation of individual collision events with the overall cooling time scale τ. The difference from this comparison indicates how energy is distributed in different degrees of freedom including both translation and rotation during the cooling.
(© 2022. The Author(s).)
Databáze: MEDLINE
Externí odkaz: