scholarly journals ANALYTIC SOLUTIONS FOR CURRENT SHEET STRUCTURE DETERMINED BY SELF-CONSISTENT, ANISOTROPIC TRANSPORT PROCESSES IN A GRAVITATIONAL FIELD

2011 ◽  
Vol 731 (1) ◽  
pp. 19 ◽  
Author(s):  
Michael L. Goodman
2020 ◽  
Author(s):  
Victor Popov ◽  
Vladimir Domrin ◽  
Helmi Malova ◽  
Elena Grigorenko ◽  
Anatoly Petrukovich

<p>The self-consistent hybrid model of a thin current sheet with a thickness about several proton gyroradii in a space plasma is proposed, taking into account multicomponent collisionless space plasma. Several plasma components are often presented in planetary magnetotails (Hermean, Martian, Terrestrial and other ones). Influence of heavy oxygen ions with different properties on current sheet structure is analyzed. It is shown that high relative concentrations of oxygen ions, as well as their relatively high temperatures and flow drift speeds lead to a significant thickening of the sheet and a formation of an additional embedding scale. For some real parameters the profiles of self-consistent current densities and magnetic field have symmetrical jumps of derivatives, i.e. sharp changes of gradients. The comparison is made with observations in the Martian magnetosphere. The qualitative agreement of simulation results with observational data is shown.</p>


2005 ◽  
Vol 14 (03n04) ◽  
pp. 687-695 ◽  
Author(s):  
B. J. AHMEDOV ◽  
A. V. KHUGAEV ◽  
N. I. RAKHMATOV

We present analytic solutions of Maxwell equations for infinitely long cylindrical conductors with nonvanishing electric charge and currents in the external background spacetime of a line gravitomagnetic monopole. It has been shown that vertical magnetic field arising around cylindrical conducting shell carrying azimuthal current will be modified by the gravitational field of NUT source. We obtain that the purely general relativistic magnetic field which has no Newtonian analog will be produced around charged gravitomagnetic monopole.


2004 ◽  
Vol 22 (7) ◽  
pp. 2547-2553 ◽  
Author(s):  
V. I. Domrin ◽  
A. P. Kropotkin

Abstract. By means of a simulation model, the earlier predicted nonlinear kinetic structure, a Forced Kinetic Current Sheet (FKCS), with extremely anisotropic ion distributions, is shown to appear as a result of a fast nonlinear process of transition from a previously existing equilibrium. This occurs under triggering action of a weak MHD disturbance that is applied at the boundary of the simulation box. In the FKCS, current is carried by initially cold ions which are brought into the CS by convection from both sides, and accelerated inside the CS. The process then appears to be spontaneously self-sustained, as a MHD disturbance of a rarefaction wave type propagates over the background plasma outside the CS. Comparable to the Alfvénic discontinuity in MHD, transformation of electromagnetic energy into the energy of plasma flows occurs at the FKCS. But unlike the MHD case, ``free" energy is produced here: dissipation should occur later, through particle interaction with turbulent waves generated by unstable ion distribution being formed by the FKCS action. In this way, an effect of magnetic field ``annihilation" appears, required for fast magnetic reconnection. Application of the theory to observations at the magnetopause and in the magnetotail is considered.


2010 ◽  
Vol 36 (10) ◽  
pp. 841-858 ◽  
Author(s):  
Kh. V. Malova ◽  
L. M. Zelenyi ◽  
O. V. Mingalev ◽  
I. V. Mingalev ◽  
V. Yu. Popov ◽  
...  

2020 ◽  
Author(s):  
Jost von der Lieth ◽  
Matthias Hort

<p>The geodynamical side of explosive volcanic eruption modelling on the one hand, as well as the petrological one on the other, have reached a high degree of sophistication and maturity independently from each other over the years. Unfortunately, adherents of one discipline often only utilize the other’s tools in a simplified and makeshift way, obscuring the full potential of their synergies. Over the past decade efforts have been made to re-integrate both approaches to the issue into a more holistic view on the sub-surface processes leading to and concurrent with explosive volcanism.<br>One of the difficulties encountered in that effort are conceptual and technical incompatibilities between thermo- and fluid-dynamic modelling toolboxes. While the tools perform well individually, they are often not suitable to work in combination in highly complex numerical models, due to interface problems impeding performance.<br>For an ongoing numerical study on transport processes within a volcanic conduit, it has been deemed necessary to re-implement an established thermodynamic model based on Holland and Powell (2011, and follow-ups) in order to a) attain the required computing performance and b) to gain sufficient petrological insight (starting from a geophysical point of view) to be able to make apt use of the tool then at hand.<br>The path to the intermediate goal of deriving the thermodynamic and transport properties (e.g. density, viscosity, heat capacity and conductivity) in a <em>self-consistent and stable</em> manner suitable for further use in a numerical fluid-dynamics model is illustrated here. The focus is on problems encountered with the petrological modelling, and on the subsequent derivation of the above properties, that are not directly available from the former results. The methods presented are general and applicable to various settings regarding volcanic chemistry and transport processes, however, they will be demonstrated on low-viscosity open-conduit systems typical for strombolian activity.</p>


2008 ◽  
Vol 15 (9) ◽  
pp. 092102 ◽  
Author(s):  
Anna G. Frank ◽  
Sergey G. Bugrov ◽  
Vladimir S. Markov

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