1、Modelling of an Inductively Coupled Plasma Torch:first stepAndr P.1,Clain S.4,Dudeck M.3,Izrar B.2,Rochette D1,Touzani R3,Vacher D.11.LAEPT,Clermont University,France2.ICARE,Orlans University,France3.Institut Jean Le Rond dAlembert,University of Paris 6,France4.LM,Clermont University,FranceCompositi
2、on in molar fractionMars97%CO2;3%N2Titan97%N2;2%CH4;1%Ar ICP Torch:atmospheric pressureLow flow of gazAssumptionsThermal equlibrium Chemical equilibriumOptical Thin plasmaSimple Case!CompositionSpectral lines,Spectroscopy measurementsTransport CoefficientsModellingThermodynamicPropertiesRadiative lo
3、ss termInteraction PotentialsCompositionSpectral lines,Spectroscopy measurementsTransport CoefficientsModellingThermodynamicPropertiesRadiative loss termInteraction PotentialsChemical and Thermal equilibrium:Gibbs Free Energy minimisationDalton LawElectrical NeutralityChemical species:MarsMonatomic
4、species(11):C,C-,C+,C+,N,N+,N+,O,O-,O+,O+Diatomic species(18):C2,C2-,C2+,CN,CN-,CN+,CO,CO-,CO+,N2,N2-,N2+,NO,NO-,NO+,O2,O2-,O2+Poly_atomic species(23):C2N,C2N2,C2O,C3,C3O2,C4,C4N2,C5,CNN,CNO,CO2,CO2-,N2O,N2O3,N2O4,N2O5,N2O+,N3,NCN,NO2,NO2-,NO3,O3 e-,solid phase:graphiteTitan:Monatomic species(13):Ar
5、,Ar+,Ar+,C,C-,C+,C+,H,H+,H-,N,N+,N+,Diatomic Species(18):C2,C2-,C2+,CN,CN-,CN+,CO,CO-,CO+,N2,N2-,N2+,NO,NO-,NO+,O2,O2-,O2+Poly_atomic species(26):C2H,C2H2,C2H4,C2N,C2N2,C3,C4,C4N2,C5,CH2,CH3,CH4,CHN,CNN,H2N,H2N2,H3N,H4N2,N3,NCN,H3+,NH4+,C2H3,C2H5,C2H6,HCCNe-,solid phase:graphite10-610-410-2100150030
6、0045006000NCC+e-NCNNHCHC2C2NC2HC2H2HCHNArC(S)H2HN2Temperature(K)Fraction molaire10-610-410-21001500300045006000CNe-NO+CNO2NNOOO2CON2CO2Temperature(K)Fraction molaireTo calculate in gas phase,we consider the temperature range 3000;15000MarsTitan10181020102210243000500070009000110001300015000C2NO2C2ON
7、O+CNCO+CO2O2N2NON+O+C+e-NCCOOTemperature(K)Concentration(m-3)MarsTitan10181020102210243000500070009000110001300015000N+NCNCHC3C2HC2CHNH2NHN2+Ar+H+C+e-ArCNCHNN2Temperature(K)Concentration(m-3)CompositionSpectral lines,Spectroscopy measurementsTransport CoefficientsModellingThermodynamicPropertiesRadi
8、ative loss termInteraction Potentials*Intensities calculation(Boltzmann distribution)MarsLine CI 2582.9 10-10 m10-510-310-11011031053000500070009000110001300015000TitanMarsTemperature(K)Intensity(W/m3/sr)CompositionSpectral lines,Spectroscopy measurementsTransport CoefficientsModellingThermodynamicP
9、ropertiesRadiative loss termInteraction PotentialsThermodynamic properties Massic density:Internal energy:e00.050.100.153000600090001200015000MarsTitanTemperature(K)Massic density(kg/m3)00.5x1081.0 x1083000500070009000110001300015000TitanMarsTemperature(K)Internal energy(J/kg)CompositionSpectral lin
10、es,Spectroscopy measurementsTransport CoefficientsModellingThermodynamicPropertiesRadiative loss termInteraction PotentialsPotential interactionsCharged-Charged:Shielded with Debye length Coulombian potential Neutral-Neutral:Lennard Jones Potential(evalaute and combining rules)Charged-Neutral:Dipole
11、 and charge transferElectrons-neutral:Bibliography and estimationsTransport coefficients:Chapman-Enskog methodElectrical conductivity:third orderViscosity coefficient:fourth orderTotal thermal conductivity k:summation of four termstranslational thermal conductivity due to the electrons,translational
12、 thermal conductivity due to the heavy species particles,internal thermal conductivity,chemical reaction thermal conductivity.0.000010.0010.11010003000500070009000110001300015000MarsTitanTemperature(K)Electrical Conductivity(S/m)0.000100.000150.000203000500070009000110001300015000TitanMarsTemperatur
13、e(K)Viscosity(Pa.s)012343000600090001200015000TitanMarsTemperature(K)Thermal Conductivity(W/m/K)Axisymmetry LTE model for inductive plasma torches LTE flow field equations USzUrGrUrGzUrFrUrFtrUzrzr RadJoulerzrrzzzzzrzrrrzrrrzzzzrzzrrrzrrrzrrPrPuurfrfPuUSqUGqUGPeuuuPuuuuUFPeuuuuuPuuUFeuuuU222000,U:co
14、nservative variable vector Fr(U),Fz(U):convective fluxes Gr(U),Gz(U):diffusive fluxes S(U):source termrurururuzuruzururuzuzuzurururuzururrzrrzrrzzzzrzrzzrrrzrrr232322322,Equation of state of the plasma considered:,PP with:internal energy defined by:221ueViscous termsrTkqzTkqrz,Conductive heat fluxes
15、Lorentz forceBJRe,0f,fzr21Joule heatingEJEPJoule0Re21Radiative loss term PRadPhysical model:assumptions-Classical torch geometry axisymmetric geometry-Local Thermodynamic Equilibrium(LTE)conditions for the plasma-Unsteady state,laminar,swirling plasma flow(tangential component)-Optically thin plasma
16、-Negligible viscous work and displacement currentMHD induction equations00JEJH,B,EBJ,Hi01JEEii B:magnetic induction H:magnetic field E:electric field J and J0:current density and source current density:magnetic permeability:electric conductivityEquations formulated in terms of electric field ENumeri
17、cal methodHydrodynamics(three steps)To obtain an approximation of the solution U on each cell,we use a fractional step technique coupling the finite volume method and the finite element method:First step:To compute the convective fluxes,we use a finite volume scheme with multislope MUSCL reconstruct
18、ion where the fluxes are calculated using a HLLC scheme.Second step:We use a Runge Kutta method to integrate the source terms.Third step:We use a finite element method to evaluate the diffusive contribution.ElectromagneticTo solve the partial differential equation,we use a standard finite element me
19、thod with a standard triangulation of the domain and the use of a piecewise linear approximation.Using the cylindrical coordinates(r,z)and assuming-invariance we obtain:EEJiEizErErrr with 1022,Basic datacompositionIntensity calculationThermodynamic propertiesFirst estimation of interaction potentialsFirst estimation of transport coefficients FutureUpgrade the interaction potentialsEstimate the accuracy need to calculate the transport coefficientsRadiative lossUnderstand the energy transfer from the inductive coilsModify the ICP torch
