@PhDThesis{Silva:2017:SoInFl,
author = "Silva, Suzana de Souza e Almeida",
title = "On the influence of nonlocal heat flux on energy transport and
balance in the solar atmosphere. (Sobre a influ{\^e}ncia do fluxo
de calor n{\~a}o local sobre o transporte e balan{\c{c}}o de
energia na atmosfera solar)",
school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
year = "2017",
address = "S{\~a}o Jos{\'e} dos Campos",
month = "2017-01-24",
keywords = "solar corona, heat flux, heat transfer, plasma heating,
magnetohydrodynamics, simulation, coroa solar, fluxo de calor,
transfer{\^e}ncia de calor, aquecimento do plasma,
magnetohidrodin{\^a}mica, simula{\c{c}}{\~a}o.",
abstract = "In the solar corona, heat flux is one of the key processes of
energy transport. Since the coronal plasma can be described as
weakly collisional, classical formulation for the heat flux might
no longer be the most accurate description. In a medium with fewer
collisions, the heat flux will have contributions not only from
neighboring particles, but also from particles coming from other
regions along the magnetic field line. Hence, a better description
of the heat flux in this context might be offered by a nonlocal
formulation. We have implemented a non local heat flux in a 3D MHD
model and we investigated its effects on the thermal evolution of
the system. We simulate the evolution of plasma and magnetic field
using this model and considering two different formulations for
heat flux: classical (local) and nonlocal one. The initial
magnetic field was obtained from a potential extrapolation of the
observed line-ofsight component of photospheric magnetic field for
AR11226. We evolved the system by imposing a field velocity at the
bottom of the simulation box which shifted footpoints of the
magnetic field lines. Then we compared the differences in the
evolution of plasma obtained using the two different formulations
for the heat flux. The inclusion of a nonlocal formulation for
heat flux leads to considerable differences in the average
temperature profile of the lower atmosphere and transition region
compared to classical formulation. There are also remarkable
differences concerning the contributions from energy transport and
from source terms to the temperature depending on the formulation
used. Our results suggest that a different heat flux formulation
affects considerably the heating dynamics and temperature
evolution of the plasma. RESUMO: Na coroa solar, o fluxo de calor
{\'e} um dos principais processos de transporte de energia. Uma
vez que o plasma coronal pode ser descrito como fracamente
colisional, a formula{\c{c}}{\~a}o cl{\'a}ssica para o fluxo de
calor pode n{\~a}o ser a descri{\c{c}}{\~a}o mais precisa. Em
um meio com menos colis{\~o}es, o fluxo de calor ter{\'a}
contribui{\c{c}}{\~o}es n{\~a}o apenas de part{\'{\i}}culas
vizinhas, mas tamb{\'e}m de part{\'{\i}}culas provenientes de
outras regi{\~o}es ao longo da linha de campo magn{\'e}tico.
Assim, uma melhor descri{\c{c}}{\~a}o do fluxo de calor neste
contexto pode ser oferecida por uma formula{\c{c}}{\~a}o
n{\~a}o-local. Implementamos um fluxo de calor n{\~a}o-local em
um modelo 3D MHD e investigamos seus efeitos na
evolu{\c{c}}{\~a}o t{\'e}rmica do sistema. N{\'o}s simulamos a
evolu{\c{c}}{\~a}o do plasma e campo magn{\'e}tico usando esse
modelo considerando as seguintes formula{\c{c}}{\~o}es para o
fluxo de calor: cl{\'a}ssico (local) e n{\~a}o-local. O campo
magn{\'e}tico inicial foi obtido a partir de uma
extrapola{\c{c}}{\~a}o potencial da componente observada da
linha de visada do campo magn{\'e}tico fotosf{\'e}rico para
AR11226. N{\'o}s evolu{\'{\i}}mos o sistema impondo
deslocamento dos footpoints das linhas de campo magn{\'e}tico. Ao
final, comparamos as diferen{\c{c}}as na evolu{\c{c}}{\~a}o do
plasma obtido utilizando as distintas formula{\c{c}}{\~o}es para
o fluxo de calor. A inclus{\~a}o de uma formula{\c{c}}{\~a}o
n{\~a}o-local para o fluxo de calor conduz a diferen{\c{c}}as
consider{\'a}veis no perfil de temperatura m{\'e}dia da
atmosfera inferior e da regi{\~a}o de transi{\c{c}}{\~a}o em
compara{\c{c}}{\~a}o com a formula{\c{c}}{\~a}o cl{\'a}ssica.
H{\'a} tamb{\'e}m diferen{\c{c}}as not{\'a}veis quanto {\`a}s
contribui{\c{c}}{\~o}es do transporte de energia e dos termos de
origem para a temperatura dependendo da formula{\c{c}}{\~a}o
utilizada. Nossos resultados sugerem que uma
formula{\c{c}}{\~a}o de fluxo de calor diferente afeta
consideravelmente a din{\^a}mica de aquecimento e a
evolu{\c{c}}{\~a}o da temperatura do plasma.",
committee = "Batista, Inez Staciarini (presidente) and Alves, Maria
Virg{\'{\i}}nia (orientadora) and Santos, Jean Carlo
(orientador) and B{\"u}chner, J{\"o}rg Artur Erick (orientador)
and Vieira, Luis Eduardo Antunes and Caldas, Iber{\^e} Luis and
Pereira, Vera Jatenco Silva",
copyholder = "SID/SCD",
englishtitle = "Sobre a influ{\^e}ncia do fluxo de calor n{\~a}o-local sobre o
transporte e balan{\c{c}}o de energia na atmosfera solar",
language = "en",
pages = "103",
ibi = "8JMKD3MGP3W34P/3N3M6F8",
url = "http://urlib.net/ibi/8JMKD3MGP3W34P/3N3M6F8",
targetfile = "publicacao.pdf",
urlaccessdate = "27 abr. 2024"
}