Energy and particle fluxes in presence of RMP in axissymetric 2D tokamak plasmas

The magnetic field model of the original IFOSIT code was improved by the analytical model of the magnetic field, which takes into account Shafranov shift, elongation, triangularity and up-down asymmetry. The spatial and velocity dependence of the CFP source can be taken into account in the renewed c...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Datum:2013
Hauptverfasser: Moskvitin, A.O., Moskvitina, Yu.K., Shyshkin, O.A., Yavorskij, V.O., Schoepf, K.
Format: Artikel
Sprache:English
Veröffentlicht: Національний науковий центр «Харківський фізико-технічний інститут» НАН України 2013
Schriftenreihe:Вопросы атомной науки и техники
Schlagworte:
Online Zugang:http://dspace.nbuv.gov.ua/handle/123456789/109248
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Назва журналу:Digital Library of Periodicals of National Academy of Sciences of Ukraine
Zitieren:Energy and particle fluxes in presence of RMP in axissymetric 2D tokamak plasmas / A.O. Moskvitin, Yu.K. Moskvitina, O.A. Shyshkin, V.O. Yavorskij, K. Schoepf // Вопросы атомной науки и техники. — 2013. — № 1. — С. 36-38. — Бібліогр.: 16 назв. — англ.

Institution

Digital Library of Periodicals of National Academy of Sciences of Ukraine
id irk-123456789-109248
record_format dspace
spelling irk-123456789-1092482016-11-22T03:03:10Z Energy and particle fluxes in presence of RMP in axissymetric 2D tokamak plasmas Moskvitin, A.O. Moskvitina, Yu.K. Shyshkin, O.A. Yavorskij, V.O. Schoepf, K. Магнитное удержание The magnetic field model of the original IFOSIT code was improved by the analytical model of the magnetic field, which takes into account Shafranov shift, elongation, triangularity and up-down asymmetry. The spatial and velocity dependence of the CFP source can be taken into account in the renewed code. New options are employed in renewed IFOSIT: calculation of energy and particle fluxes, calculation of the spatial and velocity distributions of lost and confined particles and time evolution of these distributions. Модель магнитного поля в коде IFOSIT была расширена при помощи аналитической модели магнитного поля, которая учитывает шафрановский сдвиг, эллиптичность, треугольность и асимметрию «верх-низ». В обновленном коде теперь учитывается форма профиля источника заряженных продуктов синтеза как в реальном пространстве, так и в пространстве скоростей. В новой версии кода IFOSIT реализованы новые возможности: вычисление потоков энергии и частиц, расчет распределений теряемых и удерживаемых частиц в реальном и скоростном пространствах и эволюция этих распределений. Модель магнітного поля в коді IFOSIT була розширена за допомогою аналітичної моделі магнітного поля, яка враховує шафранівський зсув, еліптичність, трикутність та асиметрію «верх-низ». У оновленому коді тепер враховується форма профілю джерела заряджених продуктів синтезу як в реальному просторі, так і в просторі швидкостей. У новій версії коду IFOSIT реалізовані нові можливості: розрахунок потоків енергії та частинок; розрахунок розподілів у реальному та швидкісному просторах для частинок, які втрачаються, та тих, які утримуються, та еволюція цих розподілів. 2013 2013 Article Energy and particle fluxes in presence of RMP in axissymetric 2D tokamak plasmas / A.O. Moskvitin, Yu.K. Moskvitina, O.A. Shyshkin, V.O. Yavorskij, K. Schoepf // Вопросы атомной науки и техники. — 2013. — № 1. — С. 36-38. — Бібліогр.: 16 назв. — англ. 1562-6016 PACS: 52.55Pi http://dspace.nbuv.gov.ua/handle/123456789/109248 en Вопросы атомной науки и техники Національний науковий центр «Харківський фізико-технічний інститут» НАН України
institution Digital Library of Periodicals of National Academy of Sciences of Ukraine
collection DSpace DC
language English
topic Магнитное удержание
Магнитное удержание
spellingShingle Магнитное удержание
Магнитное удержание
Moskvitin, A.O.
Moskvitina, Yu.K.
Shyshkin, O.A.
Yavorskij, V.O.
Schoepf, K.
Energy and particle fluxes in presence of RMP in axissymetric 2D tokamak plasmas
Вопросы атомной науки и техники
description The magnetic field model of the original IFOSIT code was improved by the analytical model of the magnetic field, which takes into account Shafranov shift, elongation, triangularity and up-down asymmetry. The spatial and velocity dependence of the CFP source can be taken into account in the renewed code. New options are employed in renewed IFOSIT: calculation of energy and particle fluxes, calculation of the spatial and velocity distributions of lost and confined particles and time evolution of these distributions.
format Article
author Moskvitin, A.O.
Moskvitina, Yu.K.
Shyshkin, O.A.
Yavorskij, V.O.
Schoepf, K.
author_facet Moskvitin, A.O.
Moskvitina, Yu.K.
Shyshkin, O.A.
Yavorskij, V.O.
Schoepf, K.
author_sort Moskvitin, A.O.
title Energy and particle fluxes in presence of RMP in axissymetric 2D tokamak plasmas
title_short Energy and particle fluxes in presence of RMP in axissymetric 2D tokamak plasmas
title_full Energy and particle fluxes in presence of RMP in axissymetric 2D tokamak plasmas
title_fullStr Energy and particle fluxes in presence of RMP in axissymetric 2D tokamak plasmas
title_full_unstemmed Energy and particle fluxes in presence of RMP in axissymetric 2D tokamak plasmas
title_sort energy and particle fluxes in presence of rmp in axissymetric 2d tokamak plasmas
publisher Національний науковий центр «Харківський фізико-технічний інститут» НАН України
publishDate 2013
topic_facet Магнитное удержание
url http://dspace.nbuv.gov.ua/handle/123456789/109248
citation_txt Energy and particle fluxes in presence of RMP in axissymetric 2D tokamak plasmas / A.O. Moskvitin, Yu.K. Moskvitina, O.A. Shyshkin, V.O. Yavorskij, K. Schoepf // Вопросы атомной науки и техники. — 2013. — № 1. — С. 36-38. — Бібліогр.: 16 назв. — англ.
series Вопросы атомной науки и техники
work_keys_str_mv AT moskvitinao energyandparticlefluxesinpresenceofrmpinaxissymetric2dtokamakplasmas
AT moskvitinayuk energyandparticlefluxesinpresenceofrmpinaxissymetric2dtokamakplasmas
AT shyshkinoa energyandparticlefluxesinpresenceofrmpinaxissymetric2dtokamakplasmas
AT yavorskijvo energyandparticlefluxesinpresenceofrmpinaxissymetric2dtokamakplasmas
AT schoepfk energyandparticlefluxesinpresenceofrmpinaxissymetric2dtokamakplasmas
first_indexed 2025-07-07T22:48:00Z
last_indexed 2025-07-07T22:48:00Z
_version_ 1837030158596308992
fulltext 36 ISSN 1562-6016. ВАНТ. 2013. №1(83) ENERGY AND PARTICLE FLUXES IN PRESENCE OF RMP IN AXISSYMETRIC 2D TOKAMAK PLASMAS A.O. Moskvitin1, Yu.K. Moskvitina2,1, O.A. Shyshkin1, V.O. Yavorskij3,4, K. Schoepf 4 1V.N. Karazin Kharkov National University, Kharkov, Ukraine; 2National Science Center “Kharkov Institute of Physics and Technology”, Kharkov, Ukraine; 3Institute for Nuclear Research, Ukrainian Academy of Sciences, Kiev, Ukraine; 4Association EURATOM-OEAW, Institute for Theoretical Physics, Innsbruck, Austria E-mail: Yu.Moskvitina@gmail.com The magnetic field model of the original IFOSIT code was improved by the analytical model of the magnetic field, which takes into account Shafranov shift, elongation, triangularity and up-down asymmetry. The spatial and velocity dependence of the CFP source can be taken into account in the renewed code. New options are employed in renewed IFOSIT: calculation of energy and particle fluxes, calculation of the spatial and velocity distributions of lost and confined particles and time evolution of these distributions. PACS: 52.55Pi INTRODUCTION AND MOTIVATION The particle transport and the confinement of fusion produced α-particles are important issues for a fusion reactor [1-2]. Resonant magnetic perturbations (RMPs) have become a powerful tool for modifying the edge transport properties and for plasma stability control in present day tokamaks. The application of non- axisymmetric RMP fields in the plasma edge region is a promising technique to suppress and mitigate ELMs for H-mode tokamak plasmas. It is confirmed by experi- ments on the DIII-D tokamak [3], and later on JET [4] and TEXTOR [5]. The alteration of transport properties of charged fusion products (CFP) induced by these per- turbations can be regarded as the crucial point for ap- proving the application of RMPs in future tokamak re- actors [6]. Note that strong effect of RMPs on the con- finement of NBI ions in ITER have been predicted re- cently in [7]. Because, a deeper understanding of how RMP fields modify charged particle dynamics; edge transport and stability are needed. In order to understand the CFP losses driven by RMPs, a specific numerical code IFOSIT (Ion Full Or- bit Simulation in Torus) has been developed [8]. The simulation is based on the test-particle approach. To calculate each particle trajectory the numerical solution of the full orbit equation is performed by the Runge- Kutta method. Coulomb collisions in the code are taken into account by a 3D Monte-Carlo operator employing a continuous spectrum of random velocity changes [9]. 1. MAGNETIC FIELD MODEL In current study, magnetic configuration of tokamak is assumed to be axisymmetric with non-circular flux surfaces. The analytical model for such configurations is described in details in [10]. It is supposed that flux sur- faces are determined by the parametric dependence of the cylindrical coordinates ( ) ( ) ( )0, cosR Rρ χ ρ ρ χ= + Δ + , (1) ( ) ( ) ( ) ( ) ( ), sin 1 cosaxZ Z k α ρ χ ρ ρ χ ρ χ= − −Λ⎡ ⎤⎣ ⎦ , (2) where R and Z represent the spatial variables of the cylindrical coordinates { }, ,R Zϕ , ρ and χ represent variables of the new flux-like coordinates { }, ,ρ χ ϕ ( )ρΔ , ( )k ρ and ( )ρΛ are flux surface parameters: the Shafranov’s shift, the elongation parameter and the triangularity parameter respectively, and α is a flux surface model parameter, 0R is vacuum vessel major radius, axZ is a Z coordinate of the magnetic axis. The coordinate ρ is a flux surface label and its value is equal to distance between the magnetic axis and the flux surface in the equatorial midplane, and χ is the analog of poloidal angle. The angle ϕ is the toroidal angle, and its value and direction coincide in both coordinate sys- tems { }, ,R Zϕ and { }, ,ρ χ ϕ . Parameters of the magnetic field model Parameter name, unit Parameter value Vacuum vessel major radius, m 0 2.89R = Magnetic axis Z coordinate, m 0.323axZ = Flux surface model parameter 0.5α = − Maximum minor plasma radius in equatorial plane, m 0.961pla = Magnetic axis Shafranov shift, m 0 0.11Δ = Elongation profile parameters 0 1.36ek = , 1 0.315ek = Triangularity profile parameter 0 0.174eΛ = Total poloidal current parame- ter, T·m 7.58J = − Magnetic configuration calculated using parameters given in Table is in good agreement with typical axi- symmetric equilibrium magnetic configuration in JET. This model was used in for calculation first orbit loss fluxes in tokamaks with non-circular cross-section, and ISSN 1562-6016. ВАНТ. 2013. №1(83) 37 examples of the flux surfaces, calculated on the basis of this model, can be found in [11]. 2. FIRST ORBIT LOSSES OF α-PARTICLES During the test runs, the dynamics of D T− first orbit losses of α − particles was simulated for the cases without RMPs. We assumed that the background plasma consists of the 50 % mixture of D- and T-ions. The number of electrons satisfies the charge neutrality con- dition e D Tn n n= + . Also, we assumed that the tempera- ture of ion and electron specie are the same. The radial profiles of density ( )en and temperature ( )eT of plasma components were chosen in the form ( ) ( )5 0 1e e Nn r n ρ= − and ( ) ( )2 0 1 NT r T ρ= − , where the subscript “0” denotes on-axis values. Using these radial profiles of the densities and temperatures, the CFP source (reaction rate) profile was calculated (Fig. 1). In order to simplify calculation of the weights, the para- bolic fit ( ) ( )521fit NS ρ ρ∝ − was used. The start positions of the test particles are uniformly distributed in the volume of the plasma trap with the help of the random numbers generator. To each particle the weight was attributed. This weight is proportional to the reaction rate in the region, where test particle starts it motion. Fig. 1. The reaction rate profiles: calculated and fitted In velocity space the test-particles were uniformly distributed on the sphere with radius equal to the birth velocity of particles. We calculated the trajectories of 100’000 particles with next initial parameters: Initial energy (3.5 MeV), velocity distribution (isotropic), simulated time (20x10-6 s), Runge-Kutta step (1/200 Tc0 ) and Monte- Carlo Collisional step (100 Tc0). To evaluate the net flux of the lost CFP, we assumed that source is constant in time and used ( ) 0 1 t dnt d t d τ τ Γ = ∫ , which sums the lost rates of fractions of CFP born at different time. The same procedure can be done for density evolution. As far as source is sta- tionary, the net flux reaches the stationary value too. In contrast to density, which is obviously increasing, be- cause only certain part of CFP is lost, and others con- tinue to be confined in trap. The ratio of the lost parti- cles can be easily estimated as 15 % (Fig. 2). In conclusion, we would like to present the poloidal (Fig. 3) and pitch (Fig. 4) distributions of the lost CFP fluxes. These distributions are in good agreement with simulation results [11, 12], theoretical predictions for the first orbit loss mechanism [11, 13, 14] and results of the experimental study of these losses [15, 16]. Fig. 2. Flux of lost particles Fig. 3. Poloidal distribution of the flux Fig. 4. Pitch distribution of the flux CONCLUSIONS The magnetic field model of the original IFOSIT code was improved by the analytical model of the mag- netic field, which takes into account Shafranov shift, elongation, triangularity and up-down asymmetry. 38 ISSN 1562-6016. ВАНТ. 2013. №1(83) The spatial and velocity dependence of the particle source can be taken into account in the renewed code now. Smooth axially symmetric 2D wall is assumed here. Optimized calculation procedures gives an opportu- nity to increase number of particles in simulated ensem- ble and to estimate statistic uncertainties. New options are employed in the renewed IFOSIT: • calculation of the energy and particle fluxes; • calculation of the spatial and velocity distribu- tions of lost and confined particles; • the time evolution of the spatial and velocity distributions. REFERENCES 1.W.W. Heidbrink, G.J. Sadler. The behaviour of fast ions in tokamak experiments // Nuclear Fusion. 1994, v. 34, № 4, p. 535-615. 2. S.J. Zweben, R.V. Budny et al. Alpha particle physics experiments in the Tokamak Fusion Test Reactor // Nu- clear Fusion. 2000, v. 40, № 1, p. 91-148. 3. T.E. Evans, R.A. Moyer, et al. Suppression of Large Edge-Localized Modes in High-Confinement DIII-D Plasmas with a Stochastic Magnetic Boundary // Physi- cal Review Letters. 2004, v. 92, № 23, p. 235003 (1-4). 4. Y. Liang, H.R. Koslowski, et al. Active control of type-I edge localized modes on JET // Plasma Physics and Controlled Fusion. 2007, v. 49, № 12B, p. B581– B589. 5. K.H. Finken, S.S. Abdullaev, et al. Improved Con- finement due to Open Ergodic Field Lines Imposed by the Dynamic Ergodic Divertor in TEXTOR // Physical Review Letters. 2007, v. 98, № 6, p. 065001 (1-4). 6. O. Schmitz, T.E. Evans, et al. Aspects of three di- mensional transport for ELM control experiments in ITER-similar shape plasmas at low collisionality in DIII-D // Plasma Physics and Controlled Fusion. 2008, v. 50, № 12, p. 124029 (1-19). 7. K. Tani, K. Shinohara, et al. Effects of ELM mitiga- tion coils on energetic particle confinement in ITER steady-state operation // Nuclear Fusion. 2012, v. 52, № 1, p. 013012. 8. Yu.K. Moskvitina, A.O. Moskvitin, et al. The fusion product losses due to resonant magnetic perturbations in toroidal plasmas // Journal of Kharkiv University, phys- ical series «Nuclei, Particles, Fields». 2011, v. 2/50/, № 955, p. 31-36. 9. K. Tani, M. Azumi, et al. Effect of Toroidal Field Ripple on Fast Ion Behavior in a Tokamak // Journal of Physical Society of Japan. 1981, v. 50, № 5, p. 1726- 1737. 10. V.A. Yavorskij, K. Schoepf, et al. Analytical models of axisymmetric toroidal magnetic fields with non- circular flux surfaces // Plasma Physics and Controlled Fusion. 2001, v. 43, № 3, p. 249 - 269. 11. A.O. Moskvitin, V.O. Yavorskij, et al. First orbit losses of charged fusion products in tokamak: flux cal- culation // Journal of Kharkоv University, physical se- ries «Nuclei, Particles, Fields».2012, v. 2/54/, № 1001, p. 4-14. 12. V. Yavorskij, Yu. Baranov, et al. Modelling of spa- tial and velocity distributions of diffusive fast ion loss in JET // 38th EPS Conf. on Plasma Phys., Strasbourg, France, June 27 – July 1. 2011, p. 4.029. 13. Ya.I. Kolesnichenko. The role of alpha particles in tokamak reactors // Nuclear Fusion. 1980. v.20, № 6, p. 727 - 780. 14. L.M. Hively, G.H. Miley. Fusion product bombard- ment of a tokamak first wall // Nuclear Fusion. 1977. v. 17, № 5, p. 1031-1046. 15. S.J. Zweben, R.L. Boivin, M. Diesso, et al. Loss of Alpha-Like MeV Fusion Products from TFTR // Nu- clear Fusion. 1990, v. 30, № 8, p. 1551-1574. 16. Yu. Baranov, I. Jenkins, et al. Evidence of anoma- lous losses of fusion products on JET // 37th EPS Con- ference on Plasma Physics, Dublin, Ireland, June 21 – 25, 2010, p. 5.141. Article received 27.09.12 ПОТОКИ ЭНЕРГИИ И ЧАСТИЦ ПРИ НАЛИЧИИ РМВ В ПЛАЗМЕ ОСЕСИММЕТРИЧНОГО 2D-ТОКАМАКА А.О. Москвитин, Ю.К. Москвитина, О.А. Шишкин, В.А. Яворский, К. Шопф Модель магнитного поля в коде IFOSIT была расширена при помощи аналитической модели магнитного поля, которая учитывает шафрановский сдвиг, эллиптичность, треугольность и асимметрию «верх-низ». В обновленном коде теперь учитывается форма профиля источника заряженных продуктов синтеза как в ре- альном пространстве, так и в пространстве скоростей. В новой версии кода IFOSIT реализованы новые воз- можности: вычисление потоков энергии и частиц, расчет распределений теряемых и удерживаемых частиц в реальном и скоростном пространствах и эволюция этих распределений. ПОТОКИ ЕНЕРГІЇ ТА ЧАСТИНОК ПРИ НАЯВНОСТІ РМЗ У ПЛАЗМІ ВІСЕСИМЕТРИЧНОГО 2D-ТОКАМАКА А.О. Москвітін, Ю.К. Москвітіна, О.О. Шишкін, В.О. Яворський, К. Шопф Модель магнітного поля в коді IFOSIT була розширена за допомогою аналітичної моделі магнітного по- ля, яка враховує шафранівський зсув, еліптичність, трикутність та асиметрію «верх-низ». У оновленому коді тепер враховується форма профілю джерела заряджених продуктів синтезу як в реальному просторі, так і в просторі швидкостей. У новій версії коду IFOSIT реалізовані нові можливості: розрахунок потоків енергії та частинок; розрахунок розподілів у реальному та швидкісному просторах для частинок, які втрачаються, та тих, які утримуються, та еволюція цих розподілів.