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A model for inductive plasma wind tunnelsMagin, Thierry E. B. 10 June 2004 (has links)
A numerical model for inductive plasma wind tunnels is developed. This model provides the flow conditions at the edge of a boundary layer in front of a thermal protection material placed in the plasma jet stream at the outlet of an inductive torch. The governing equations for the hydrodynamic field are derided from the kinetic theory. The electromagnetic field is deduced from the Maxwell equations. The transport properties of partially ionized and unmagnetized plasma in weak thermal nonequilibrium are derived from the Boltzmann equation. A kinetic data base of transport collision integrals is given for the Martian atmosphere. Multicomponent transport algorithms based upon Krylov subspaces are compared to mixture rules in terms of accuracy and computational cost. The composition and thermodynamic properties in local thermodynamic
equilibrium are computed from the semi-classical statistical mechanics.
The electromagnetic and hydrodynamic fields of an inductive wind tunnel is presented. A total pressure measurement technique is thoroughly investigated by means of numerical simulations.
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A model for inductive plasma wind tunnelsMagin, Thierry 10 June 2004 (has links)
A numerical model for inductive plasma wind tunnels is developed. This model provides the flow conditions at the edge of a boundary layer in front of a thermal protection material placed in the plasma jet stream at the outlet of an inductive torch. The governing equations for the hydrodynamic field are derided from the kinetic theory. The electromagnetic field is deduced from the Maxwell equations. The transport properties of partially ionized and unmagnetized plasma in weak thermal nonequilibrium are derived from the Boltzmann equation. A kinetic data base of transport collision integrals is given for the Martian atmosphere. Multicomponent transport algorithms based upon Krylov subspaces are compared to mixture rules in terms of accuracy and computational cost. The composition and thermodynamic properties in local thermodynamic<p>equilibrium are computed from the semi-classical statistical mechanics.<p>The electromagnetic and hydrodynamic fields of an inductive wind tunnel is presented. A total pressure measurement technique is thoroughly investigated by means of numerical simulations.<p> / Doctorat en sciences appliquées / info:eu-repo/semantics/nonPublished
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[en] MODELLING AND NUMERICAL SIMULATION OF THE TWO PHASES FLUX AND TRANSPORT MULTICOMPONENT IN THE POROUS MEDIUM WITH NO ISOTERMIC-CHEMICAL INTERACTION / [pt] MODELAGEM E SIMULAÇÃO NUMÉRICA DO FLUXO BIFÁSICO E DO TRANSPORTE MULTICOMPONENTE EM MEIOS POROSOS COM INTERAÇÃO TERMO-QUÍMICAJULIO CESAR DA SILVA 18 February 2005 (has links)
[pt] Este trabalho apresenta o estágio atual do desenvolvimento
de uma ferramenta
numérica para simulação e análise do fluxo bifásico e do
transporte multicomponente
e de calor em meios porosos com interação química em duas
dimensões.
O programa desenvolvido foi baseado no UNSATCHEM_2D escrito
em
linguagem Fortran. A discretização das equações
diferenciais parciais é feita em
elementos finitos no espaço e em diferenças finitas no
tempo. Uma interface grá-
fica foi criada em linguagem Lua para a entrada dos dados e
visualização dos
resultados. Esta interface foi baseada no programa Mtool do
TecGraf. O objetivo
do trabalho foi implementar uma ferramenta que acoplasse
diferentes processos
em meios porosos: fluxo bifásico, transporte de solutos,
processos químicos e
temperatura. A ferramenta desenvolvida deverá ser útil em
análises de problemas
ambientais. Em particular, o enfoque deste trabalho é no
acoplamento de
processos químicos. Para isto, uma rotina de especiação
química foi acoplada à
cinética química com relevância na oxidação mineral. Para
resolver o problema
da especiação química, o programa Phreeqc foi utilizado. O
trabalho apresenta
detalhes dos processos de análise, de suas equações
relevantes e da implementação
numérica. No estágio atual de desenvolvimento, o programa é
capaz de
avaliar o transporte de metais e, em particular, a
simulação da drenagem ácida
em barragens de rejeito e pilhas de estéril sob condições
complexas. Exemplos
de validação e ilustrativos são mostrados e discutidos. São
sugeridas algumas
possibilidades de futuros acoplamentos à ferramenta
numérica desenvolvida. / [en] This work presents the present stage of development of a numerical platform for
simulation and analysis of two-phase flow and of, non isotermic, multicomponent
transport in porous media with chemical interaction in two dimensions. The
developed computer code is based on the UNSATCHEM_2D code written in
Fortran language. The discretization of the partial differential equations is done
by finite elements at the space and in finite difference at the time. A graphical
interface was created in language Lua for the input of the data and result visualization.
This interface was based on the program TecGraf’s Mtool. The purpose
of the work was to construct a numerical tool that couples different processes
in porous media: flow (two-phase), transport of solutes, chemical processes and
temperature. The developed tool should be useful in the analysis of environmental
problems. In particular, the work focused on the coupling of chemical
processes. For this, a chemical speciation routine was coupled to chemical kinetics
with relevance to mineral oxidation. In order to solve the chemical speciation
problem, the program Phreeqc was used. The work presents details of the analyzed
processes, their relevant equations and of the numerical implementation.
At the present stage of development, the computer program is able to evaluate the
transport of metals and, at particular, the simulation of the acid mine drainage at
tailings discharge and waste rock piles under complex conditions. Validation and
illustrative examples are shown and discussed. Possibilities of future additions to
the developed tool are suggested.
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