2023
Polytropic representation of the kinetic pressure tensor of non-ideal magnetized fluids in equilibrium toroidal structures
CREMASCHINI, Claudio, Jiří KOVÁŘ, Zdeněk STUCHLÍK a Massimo TESSAROTTOZákladní údaje
Originální název
Polytropic representation of the kinetic pressure tensor of non-ideal magnetized fluids in equilibrium toroidal structures
Autoři
CREMASCHINI, Claudio (380 Itálie, domácí), Jiří KOVÁŘ (203 Česká republika, domácí), Zdeněk STUCHLÍK (203 Česká republika, domácí) a Massimo TESSAROTTO (380 Itálie, domácí)
Vydání
PHYSICS OF FLUIDS, 2023, 1070-6631
Další údaje
Jazyk
angličtina
Typ výsledku
Článek v odborném periodiku
Obor
10308 Astronomy
Stát vydavatele
Spojené státy
Utajení
není předmětem státního či obchodního tajemství
Odkazy
Kód RIV
RIV/47813059:19630/23:A0000298
Organizační jednotka
Fyzikální ústav v Opavě
UT WoS
000912154000009
Klíčová slova anglicky
Non-ideal fluids;Pressure tensors; Microscopic kinetics;Chapman-Enskog expansion;fluid plasma;accretion-disk;
Příznaky
Mezinárodní význam, Recenzováno
Změněno: 26. 2. 2024 13:19, Mgr. Pavlína Jalůvková
Anotace
V originále
Non-ideal fluids are generally subject to the occurrence of non-isotropic pressure tensors, whose determination is fundamental in order to characterize their dynamical and thermodynamical properties. This requires the implementation of theoretical frameworks provided by appropriate microscopic and statistical kinetic approaches in terms of which continuum fluid fields are obtained. In this paper, the case of non-relativistic magnetized fluids forming equilibrium toroidal structures in external gravitational fields is considered. Analytical solutions for the kinetic distribution function are explicitly constructed, to be represented by a Chapman-Enskog expansion around a Maxwellian equilibrium. In this way, different physical mechanisms responsible for the generation of non-isotropic pressures are identified and proved to be associated with the kinetic constraints imposed on single and collective particle dynamics by phase-space symmetries and magnetic field. As a major outcome, the validity of a polytropic representation for the kinetic pressure tensors corresponding to each source of anisotropy is established, whereby directional pressures exhibit a specific power-law functional dependence on fluid density. The astrophysical relevance of the solution for the understanding of fluid plasma properties in accretion-disk environments is discussed.