Application of a hybrid collisional radiative model to recombining argon plasmas

Benoy, D.A.; Mullen, J.A.M. van der; Sanden, M.C.M. van de; Sijde, B. van der; Schram, D.C.

doi:10.1016/0022-4073(93)90053-k

Cited by 19 publications

(8 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Berthelot and Bogaerts developed a lumped-levels model to avoid solving equations for all individual CO 2 vibrational levels, demonstrating that a three-groups model is able to (more or less) reproduce the asymmetric mode vibrational distribution function of CO 2 . Similar procedures were applied in the past to compress the computational requirements of recombining plasma models . In the paper by de la Fuente et al, a reduction methodology for STS kinetics was illustrated, whereby the asymmetric stretching vibrational mode levels are lumped within a single group or fictitious species.…”

Section: Introductionmentioning

confidence: 99%

Insight into CO₂ Dissociation in Plasma from Numerical Solution of a Vibrational Diffusion Equation

2017

View full text Add to dashboard Cite

The dissociation of CO2 molecules in plasmas is a subject of enormous importance for fundamental studies and in view of the recent interest in carbon capture and carbon-neutral fuels. The vibrational excitation of the CO2 molecule plays an important role in the process. The complexity of the present state-to-state (STS) models makes it difficult to find out the key parameters. In this paper we propose as an alternative a numerical method based on the diffusion formalism developed in the past for analytical studies. The non-linear Fokker-Planck equation is solved by the timedependent diffusion Monte Carlo method. Transport quantities are calculated from STS rate 2 coefficients. The asymmetric stretching mode of CO2 is used as a test case. We show that the method reproduces the STS results or a Treanor distribution depending on the choice of the boundary conditions. A positive drift, whose energy onset is determined by the vibrational to translational temperature ratio, brings molecules from mid-energy range to dissociation.Vibrational-translational energy transfers have negligible effect at the gas temperature considered in this study. The possibility of describing the dissociation kinetics as a transport process provides insight towards the goal of achieving efficient CO2 conversion. IntroductionPlasma-assisted gas conversion techniques are widely considered as efficient building blocks in a future energy infrastructure which will be based on renewable but intermittent electricity sources. In particular CO2 dissociation in high-frequency plasmas is of interest in carbon capture and utilization process chains for the production of CO2-neutral fuels 1 . In this case, the vibrational excitation of the CO2 molecule plays an important role in the energy efficient non-equilibrium dissociation kinetics, however several aspects of the dissociation kinetics in plasmas are still unclear.Dissociation takes place when collisions between molecules and electrons, as well as intermolecular collisions, provide enough energy to lead an already excited molecule into the continuum region thereby producing CO and O. The state-to-state (STS) approach 2,3 allows to calculate very accurate reaction rates by considering any vibrational state as an individual species.This amounts to solve the so-called Master Equation (ME) for the populations of vibrational states 2,4 : The ME is actually a system of n non-linear ODEs (Ordinary Differential Equations)

show abstract

Section: Introductionmentioning

confidence: 99%

Insight into CO₂ Dissociation in Plasma from Numerical Solution of a Vibrational Diffusion Equation

2017

View full text Add to dashboard Cite

show abstract

“…The contributions n crm and n ext lead to two additive source contributions as well, as can be seen from equation (11). This equation relates the total production to the transport term; after substitution of equation ( 12) we get…”

Section: Particle Source Termsmentioning

confidence: 98%

“…Note that this includes radiation originating from the LC-levels, whose densities follow indirectly from the TS levels. This contribution is commonly completely ignored in high electron density CRM's [10][11][12]. Again, let us see how this reduces to a more familiar form in the absence of external processes, that is, S ext = 0.…”

Section: Radiation Lossesmentioning

confidence: 99%

“…For given values of n t the equations for n l have to be calculated numerically with a nonlinear equation solver. Equation (11) can then be used to calculate the corresponding sources.…”

Section: Process Coefficient Meaningmentioning

confidence: 99%

“…In this work we have used a more sophisticated cut-off technique, which is based on the known deviation from Saha equilibrium for levels which are dominated by stepwise excitation processes. This technique is discussed thoroughly in [1,11], and has also been used in our previous paper about mercury collisional radiative models [2]. The number of levels that needs to be taken into account depends on the plasma parameters and the peculiarities of the atomic system under study.…”

Section: Cut-off Proceduresmentioning

confidence: 99%

See 2 more Smart Citations

Collisional radiative models with multiple transport-sensitive levels - application to high electron density mercury discharges

Dijk¹,

Hartgers²,

Jonkers

et al. 2001

J. Phys. D: Appl. Phys.

View full text Add to dashboard Cite

In this paper some of the basic concepts in collisional radiative modelling of plasmas will be generalized. A mathematical framework is presented which is suitable for systems with an arbitrary number of transport sensitive and quasi-steady or local chemistry states. The mathematical formulation presented here leads to straightforward extensions of quantities which have been previously introduced for systems in which only the atom and ion ground states were dealt with explicitly. These are the net coefficients of ionization and recombination, the effective specific emission coefficients, and the relative overpopulation coefficients. For a given set of transport-sensitive densities these quantities can be used to calculate the particle and radiation source terms and the atomic state distribution function. Furthermore the use of matrix-vector calculus has led to concise, insightfull, yet general expressions. And although some explicit references will be made to plasmas which are governed primarily by processes involving electrons, most of the theory presented here can be carried over to other systems without great difficulty. As an example, a collisional radiative model for mercury will be presented for discharges with electron temperatures between 0.75 eV and 2 eV and electron densities between 1018 m-3 and 1020 m-3. In the current model six transport-sensitive levels have been assumed. Another 13 excited mercury states are taken into account implicitly; ladderlike excitation and ionization will be shown to be of major importance for discharges in this parameter range. The model allows the incorporation of heavy-particle reactions and a full treatment of the transfer of resonant radiation.

show abstract

Heat transfer—a review of 1993 literature

Eckert

Goldstein

Ibele

et al. 1996

International Journal of Heat and Mass Transfer

View full text Add to dashboard Cite

Application of a hybrid collisional radiative model to recombining argon plasmas

Cited by 19 publications

References 22 publications

Insight into CO₂ Dissociation in Plasma from Numerical Solution of a Vibrational Diffusion Equation

Insight into CO₂ Dissociation in Plasma from Numerical Solution of a Vibrational Diffusion Equation

Collisional radiative models with multiple transport-sensitive levels - application to high electron density mercury discharges

Heat transfer—a review of 1993 literature

Contact Info

Product

Resources

About

Application of a hybrid collisional radiative model to recombining argon plasmas

Cited by 19 publications

References 22 publications

Insight into CO2 Dissociation in Plasma from Numerical Solution of a Vibrational Diffusion Equation

Insight into CO2 Dissociation in Plasma from Numerical Solution of a Vibrational Diffusion Equation

Collisional radiative models with multiple transport-sensitive levels - application to high electron density mercury discharges

Heat transfer—a review of 1993 literature

Contact Info

Product

Resources

About

Insight into CO₂ Dissociation in Plasma from Numerical Solution of a Vibrational Diffusion Equation

Insight into CO₂ Dissociation in Plasma from Numerical Solution of a Vibrational Diffusion Equation