Overview of equations and Overview of equations and assumptions assumptions Elena Khomenko, Manuel Collados, Elena Khomenko, Manuel Collados, Antonio Díaz Antonio Díaz Departamento de Astrofísica, Universidad de La Laguna and Instituto de Astrofísica de Canarias (IAC), La Laguna, Tenerife (Spain). http://www.iac.es/ proyecto/spia/
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Overview of equations and assumptions Elena Khomenko, Manuel Collados, Antonio Díaz Departamento de Astrofísica, Universidad de La Laguna and Instituto.
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Overview of equations and assumptionsOverview of equations and assumptions
Elena Khomenko, Manuel Collados, Antonio DíazElena Khomenko, Manuel Collados, Antonio Díaz
Departamento de Astrofísica, Universidad de La Laguna and Instituto de Astrofísica de Canarias (IAC),
La Laguna, Tenerife (Spain).
http://www.iac.es/proyecto/spia/
Elena Khomenko
DDegree of egree of IIonization in VAL-C onization in VAL-C mmodelodel
Chromosphere
Photosphere
Elena Khomenko
DDegree of egree of IIonization in VAL-C onization in VAL-C mmodelodel
phot
osph
ere
chro
mos
pher
e
ni
nN
Elena Khomenko
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Important for magnetized Important for magnetized photosphere and chromospherephotosphere and chromosphere
BRelative motions between electrons, ions and neutrals (Hall effectHall effect and Ambipolar diffusionAmbipolar diffusion)
produce additional important sources of heating.
Additional diffusitivy due to collisions between ions and neutrals is 5-6 orders of magnitude
larger than the usual Coulomb diffusivity (Reynolds number around 1-10Reynolds number around 1-10).
Characteristic scales in a partially ionized plasma depend on the degree of ionization
reaching 10 km10 km and 1 sec1 sec for the solar atmosphere.
MMulti-fluidulti-fluid aapproximationpproximation
Elena Khomenko
HHow detailedow detailed? ?
MHDQuasi-MHD: single fluid
2- or 3-fluid MHD
Kinetic equations; motion of individual
particles
Depending on scales of phenomena to study, and number of particles.
Events on scales below 10 km10 km & 1 sec1 sec and chromospheric density & neutral fraction probably require multi-fluid approach.
Elena Khomenko
EEquations for quations for iindividual ndividual sspeciespecies