Diapositiva 1

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Universidad Simón Bolívar Departamento de
Ciencias de lo Materiales Departamento de Física
Centro de Ingeniería de Superficies
NUMERICAL SIMULATION OF A THERMAL PLASMA FLOW
CONFINED BY MAGNETIC MIRROR IN A CYLINDRICAL
REACTOR
Authors Gabriel Torrente Julio Puerta Norberto
Labrador
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ANTECEDENTS
First Plasma reactor designed and constructed
with a grant by FONACIT project of AlN synthesis
in a thermal plasma reactor
Thermal Plasma Reactor with Expansion Chamber
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RESULTS OF ANTECEDENTS
8.a
8.b
Problem Few Thermal Carbonitridation level of
Al2O3
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Solution for the enhancement of nitridation 1.
Increasing the power of the thermal plasma. 2.
Increasing the resident time of the powders in
the high thermal zones of reactor. 3. Decreasing
the thermal energy loss of reactor.
the energy cost of the process increase
the energy cost of the process does not Increase
Then, it is convenient to 1.Design the thermal
plasma reactor in fluidized bed for increase the
resident time. 2. Confine the thermal plasma
flow by magnetic mirror for decrease the energy
loss.
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New design
Wall Reactor
Refractory Tube
Graphite tube
Magnetic Coils
Plasma Torch
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First step
NUMERICAL SIMULATION OF A THERMAL PLASMA FLOW
CONFINED BY MAGNETIC MIRROR IN A CYLINDRICAL
REACTOR
The numerical simulation of this thermal
axisymmetry plasma jet in magnetic mirror is
carried out using two-temperature model to study
how changes the electron density and the plasma
flux whit the temperature, pressure and with the
applied magnetic fields.
Control Volume
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Governing Equation
Initial Conditions
Where the cross section impact and average
initial temperatura are
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Boundary conditions
In the Central Axel
In the reactor wall
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State Equation
Continuity Equation
Momentum Conservation Equations (Navier-Stoke
Equations)
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Energy Conservation Equations
Where
Energy transport from the electron to plasma gas
Collision frequency
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Saha Ionization Equation
Ohm Generalized Law
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Maxwell Equations
Biot-Savart Law
Hypothesis and Data
1. Pressure, Heat Capacity Gas (Cpg), Viscosity
Gas (h) and Thermal Conductivity Gas (K) are
constants. 3. The dissociation energy is
neglected. 4. Axial Symmetry 5. Only magnetic
field in axial direction 6. Power Plasma Torch
10,5 KW mass flow 13,2 lpm of Nitrogen, Bzmax
0,3 T, Ionization Energy 15,4 eV
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Results
Axial velocity Profile
Pressure 1 Torr (133 Pa)
Pressure 1 atmosphere (101325 Pa)
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Plasma Temperature Profile
Pressure 1 Torr (133 Pa)
Pressure 1 atmosphere (101325 Pa)
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Electronic Temperature Profile
Pressure 1 Torr (133 Pa)
Pressure 1 atmosphere (101325 Pa)
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Density Plasma Profile
Pressure 1 Torr (133 Pa)
Pressure 1 atmosphere (101325 Pa)
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Electronic Density Profile
Pressure 1 Torr (133 Pa)
Pressure 1 atmosphere (101325 Pa)
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Z ionization Profile
Pressure 1 Torr (133 Pa)
Pressure 1 atmosphere (101325 Pa)
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Plasma Torch
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Conclusions
The axial velocity has few changed with the
pressure. The Plasma Temperature has few changed
with the pressure. The electronic temperature
has few increasing with the vacuum The Plasma
and Electronic densities decreases with the
vacuum. Z ionization increases with the vacuum.