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Molecular Data in Tokamak edge Modelling D. Tskhakaya Association EURATOM-ÖAW, University of Innsbruck, A-6020 Innsbruck, Austria Andronikashvili Institute of Physics, 0177 Tbilisi, Georgia. Outline. Molecular sources Processes involving molecules Requirements to the molecular data
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Molecular Data in Tokamak edge Modelling D. Tskhakaya Association EURATOM-ÖAW, University of Innsbruck, A-6020 Innsbruck, Austria Andronikashvili Institute of Physics, 0177 Tbilisi, Georgia D. Tskhakaya ADAC meeting, Cadarache 24.9.2012
Outline • Molecular sources • Processes involving molecules • Requirements to the molecular data • Needs for kinetic modeling of the plasma edge • Conclusions D. Tskhakaya ADAC meeting, Cadarache 24.9.2012
JET Molecular sources in the SOL Plasma-facing components (PFC): chamber walls, divertor plates, RF antennas, … D. Tskhakaya ADAC meeting, Cadarache 24.9.2012
Molecular sources in the SOL „Conventional“ tokamaks C (CFC), Fe, … AUG, DEMO (?) W JET, ITER Be W Tokamaks with liquid walls Gas puffing (e.g. D2) Li D. Tskhakaya ADAC meeting, Cadarache 24.9.2012
Molecular sources in the SOL Plasma recycling D+ A Wall Surface C, W :A= D2 (>90%) Be: ? Li: R~0 Wall For DT operation A= D2, DT, T2 At low energies isotope effects might be important! H2+ + H2 H3+ + H D3+, T3+, TD2+, DT2+ D. Tskhakaya ADAC meeting, Cadarache 24.9.2012
Molecular sources in the SOL Impurity sputtering B A Wall Surface C (chemical sputtering): B= Dm A= CnDk W: ? Be [Björkas PSI 2012]: B= D A= BeD (<60%) A= BeD2(<40%) Wall For DT operation A= BeD, BeT, BeD2, BeT2 D. Tskhakaya ADAC meeting, Cadarache 24.9.2012
Molecular sources in the SOL Impurity seeding, etching N2 , O2 , NO2 Molecules to be taken into the account in fusion plasma edge modeling D2, DT, T2 , D3+, T3+, TD2+, DT2+ BeD, BeT, BeD2, BeT2 N2 , O2 , NO2 CnDmTk D. Tskhakaya ADAC meeting, Cadarache 24.9.2012
Processes in the plasma edge involving molecules e + M e + M Elastic e + M e + M* Excitation (electronic, vibrational, rotational) e + M 2e + M+ Ionization e + M e + A + B Dissociation e + M e + A+ + B Dissociative ionization e + M+ A + B Dissociative recombination e + M A- + B Dissociative attachment A + M A + M Elastic A + M A + M* Excitation A+ + M A + M+ Charge exchange A + M+ A+ + M Charge exchange A + M A + B + G Dissociation A- + M A + M + e Electron detachment with molecule M - molecule (in some excitation/ionization state) A – molecule, ot atom (in some excitation/ionization state) D. Tskhakaya ADAC meeting, Cadarache 24.9.2012
Requirements to the data Fluid, or fluid/kinetic models (e.g. B2-SOLPS, ERO, EIRENE, …) A Maxwell-distributed particle pool M B Rate coefficients (averaged over initial/final excitation-states) are required Data source: ADAS, … D. Tskhakaya ADAC meeting, Cadarache 24.9.2012
Requirements to the data Full kinetic models (PIC/MC) a a c a c d b d b b e Data source: any available Differential cross-sections for H++H2 elastic collision implemented in BIT1 code D. Tskhakaya ADAC meeting, Cadarache 24.9.2012
Rate coefficients vs differential CS Electron/ion VDFs in the SOL[Tskhakaya CPP 2012] The VDFs are strongly(!) non-Maxwellian during the ELMs OMP 10 cm SE D. Tskhakaya ADAC meeting, Cadarache 24.9.2012
Full kinetic models Massively parallel codes (such as BIT-N) are able to simulate few of different particle species (including metastables) with thousands of A&M processes. Density profiles from the divertor plasma simulation. Serial PIC/MC code with ~100 of different A&M processes. D. Tskhakaya ADAC meeting, Cadarache 24.9.2012
For (kinetic) modelers collection of the appropriate A&M&S data is the most complicated task! Cross-sections for H2+ + H2 charge-exchange collision from different sources. D. Tskhakaya ADAC meeting, Cadarache 24.9.2012
Sensitivity of simulation results to the A&M data a) b) Power loads to the outer divertor during 0.15 MJ type-I ELM at JET #74380. a) Constant recycling coefficient RD= 0.99; b) Energy-dependant recycling coefficientRD(E). D. Tskhakaya ADAC meeting, Cadarache 24.9.2012
EFDA Task Force ITM Task AMNS • Collection and verification of the Molecular data • Implementation into the corresponding AMNS data structure • in a standardized way • Support of different codes in implementation of • corresponding routines for accessing AMNS data Status: data structure is ready for implementation of molecular rate coefficients and differential CS of practically any complexity. There is a possibility to update the data structure for metastables. D. Tskhakaya ADAC meeting, Cadarache 24.9.2012
Conclusions • Molecular processes represent important part of predictive plasma edge modeling • While data for rate coefficients are available, the corresponding differential CS are hard to find • There is no systematic approach to metastables. How to include them into the plasma edge models? Independently of the complexity and format of the provided validated molecular data, it will be used by us (i.e. modelers)! D. Tskhakaya ADAC meeting, Cadarache 24.9.2012
ELMs simulations 0.1-1 ms 10-100 ms Filaments of small and large ELMs at MAST (UK) D. Tskhakaya ADAC meeting, Cadarache 24.9.2012
Differential cross-sections e + H = 2e + H+ Angular differential cross sections D. Tskhakaya PWI TF, JET Culham, 13-15 July 2011 D. Tskhakaya ADAC meeting, Cadarache 24.9.2012