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Status of Integrated Tokamak Modeling activity in RUSSIA (Since May 2007). Good news!. Government approval of RF fusion program till 2050 with budget ~20 G$ (August 2007) Rosatom put fusion plasma simulation in the list of supported projects (September 2007).
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Status of Integrated Tokamak Modeling activityin RUSSIA(Since May 2007)
Good news! • Government approval of RF fusion program till 2050 with budget ~20 G$ (August 2007) • Rosatom put fusion plasma simulation in the list of supported projects (September 2007) IMAGE session, Naka, October 2007
Institutions Involved in ITM activity coordinated by Kurchatov Institute НИИЭФА Им. Ефремова IMAGE session, Naka, October 2007
Main Codes Auxiliary Heating & CDOGRAY, PSTELION, ANTRES Particle Motion & KineticsDRIFT, FPP-3D,VENUS-dF EquilibriumSPIDER, PET MHD StabilityKINX, NFTC Scenario ASTRA DINA Control Impurity radiation & transportZIMPUR Plasma Initiation SCENPLINT TRANSMAK Data Analysis, Neural Network, Visualization, etc.:SCoPEShell NNTMM, VIP, CLUNAVT 3D structuresKLONDIKE, TYPHOON IMAGE session, Naka, October 2007
Inverse Problems – MSU proposals 1.Equilibrium reconstruction A key difference of the presented approach from traditional consists of two features. Usage of the Ohm law along with the Grad-Shafranov equation and assumption of known plasma boundary. Larger amount of input data substantially increases the accuracy of the inverse problem solution. Toroidal current density, its components and poloidal flux function in the equatorial planeZ = 0 (Up) and dependenceof p andF derivatives on normalised flux (down).Dashed line is appropriate to solution of the direct problem, solid – to the inverse with ±15 % (10% for down figure)random error in measurements of IMAGE session, Naka, October 2007
Inverse problems - 2 • 2. Reconstruction of the multiharmonicspectrum and spatial structure of plasma oscillations (SXR, magnetic diagnostics data) • 3. Reconstruction of the radiation source distribution from photo or video data (SOL and divertor) • 4. Plasma boundary reconstruction from video data • 5. Reconstruction of the Fast ion distribution from NPA data IMAGE session, Naka, October 2007
General Strategy is parallel development of compatible modules and integrated code • Integration based on transport code (ASTRA + DINA) • Modules: 1)Physics: Fixed/Free boundary equilibrium, Ideal/Resistive/Drift/EP MHD stability, Auxiliary Heating/CD, Impurity dynamics, Runaways, Energetic Ion effects, etc. 2)Engineerings: ITER systems, controllers, etc. 3)Diagnostics: EP, Ha, neutron, magnetic, reflectometry… • ONLY FREE SOFTWARE to be used for ITM Integrating code Modules ITER Simulators Ultimate Goal is ITER simulators IMAGE session, Naka, October 2007
Tactics:(survival) Urgent tasks specified by ITER IO are the principal driver of ITM in RF • Plasma start up and termination • RWM control • DNB design specifications • … Involve computing science and technology specialist into ITM activity (MSU profs. and students) • Grid and MPI (ASTRA-grid (potential tool for experimental strategy development, Fast Ions – OFMC (non symmetrical perturbations (TBM) require huge CPU time, δf – multi-D distribution function) • ITM Workflow (Kepler, CPO, other options) – first meeting next week • Data manning Get closer to the credited diagnostics development IMAGE session, Naka, October 2007
Plasma Start up and Termination IMAGE session, Naka, October 2007
Development of scenarios of plasma start up (incl. initiation) and termination, in particular, design and simulation of ITER PF system • Collaboration between Efremov Inst. And Kurchatov inst. • CODES involved (Efremov Inst.): SCENPLINT – 0D plasma initiation model (prefilled gas pressure, impurity content, ECRF power, plasma resistance) TRANSMAK – PF system characteristics, currents induced in the conducting elements, model of the power supply IMAGE session, Naka, October 2007
DINA code • Free boundary equilibrium solver • 1D transport • Eddy currents in VV • Model of power supply • Feed back and feed forward control of plasma current, plasma position and shape IMAGE session, Naka, October 2007
DINA simulation of the VDE IMAGE session, Naka, October 2007
Integrated code for simulation of plasma start up and termination • DINA + SCENPLINT + TRANSMAK = New Code • Revised models for neutrals (1D instead of 0D), plasma initiation with smooth transition to current rump-up stage, impurity radiation and transport. • User interfaces: compatibility with ASTRA shell • Validation against experimental data • Comparison with ASTRA simulation IMAGE session, Naka, October 2007
RWM Control in ITER IMAGE session, Naka, October 2007
Development of new 3D code for simulation of RWM control in ITER • Theory background: review of the existing models, plasma rotation effects, error field amplifications, etc. (V.D. Pustovitov, to be presented at ITPA MHD group next week) • 2D KINX-RWM to be upgraded and combined with 3D transient electromagnetic analysis of tokamaks – TYPHOON code IMAGE session, Naka, October 2007
KINX - RWM • KINX-RWM is capable to treat realistic divertor plasma configurations with self-consistent treatment of the separatrix at the plasma boundary. • Thoroughly benchmarked against the analytic models and other stability codes. • Proved to provide high accuracy of the computed growth rates, mode structures and transfer functions describing evolution of RWM in the presence of active control Levels of normal displacements (left) and perturbed magnetic field along the first wall. IMAGE session, Naka, October 2007
KINX + TYPHOON 3D RWM • TYPHOON is electromagnetic analysis of complex 3D conducting structures, used for ITER magnetic system design • The experience already gained from the KINX-TYPHOON coupling for the ideal MHD growth rate calculations, taking into account the 3D VV with port openings, will allow fast and efficient implementation of the multi-mode 3D RWM code • High flexibility of the 3D conductor description inherent to the TYPHOON and vast expertise in the ITER plasma control will allow reliable estimates of the feedback coil efficiency for different options of the control system IMAGE session, Naka, October 2007
Fast Particle Physics IMAGE session, Naka, October 2007
Main problems from FPP to contribute in ITM • Confinement, loss (FW loading), power and momentum transfer to plasma components (heating, CD, plasma rotation) • FP driven instabilities (AE family, EPM etc.) • Self consistent simulation of instabilities and transport • FP diagnostics simulation IMAGE session, Naka, October 2007
FPP codes -1: OFMC code DRIFT • Anomalous transport and losses of fast ions (ripple, MHD perturbations) • Heat loads on plasma facing elements • MAPPING option with time step equal to bounce period (1/2 for trapped ions) • NBI module • ICRF heating • FI distribution function • Power and momentum transfer to plasma species • FI Diagnostics (NPA, scintillators, MSE, CX) FW loading due to perpendicularly injected DNB IMAGE session, Naka, October 2007
Fast Ion Distribution Function NBI distribution function and NPA spectrum in JET IMAGE session, Naka, October 2007
Comments on ITER NBI and ICRF modules NBI • NUBEAM – 2D particle orbits, thus ripple effect is treated in terms of stochastic diffusion loss, AE – in a similar way (i.e. in a form of effective diffusion coefficients). Applicability is limited. • ASTRA-NBI – zero banana, no bounce averaging – potential overestimation of the off-axis CD Solution – approximation of the DRIFT results for transport. Implementation of the bounce average technique (already done in MAPPING part) into ASTRA-NBI ICRF • ICRF effect is treated in assymptotic approximation, wrong near the axis, errors in simulation of the central ICRF heating. • Needs selfconsistent simulation with Full Wave modelling IMAGE session, Naka, October 2007
FPP codes-2: Fokker-Planck Package Three-Dimensionalcode FPP-3D • Solves 3D drift orbit averaged kinetic equation, no limits on orbit width (esp. important for RS scenario) • Calculates radial particle, momentum and energy fluxes, bootstrap-current electron and ion components, etc. • Non-linear problems can be solved. • Fusion alphas, NBI and ICRF heated ion dynamics • Particle fluxes into lost ion detectors and NPA • Solution of inverse kinetic problems. Fusion alphas in JET experiment DRIFT FPP-3D simplified fast ion modules for ASTRA-DINA Full set of NBI simulators: Monte Carlo, 3D, 2D, 1D Fokker Plank IMAGE session, Naka, October 2007
Alfvén mode stability in ITER Alfven continuum (left) and gap mode radial structure in ITER inductive scenario Selfconsistent model for the Alfven mode evolution and associated fast ion transport (KINX + DRIFTASTRA; KINX+(VENUS+df)) is under development. FP drive and dumping mechanisms to be included. Consistency with equilibrium calculations, setting the separatrix shape could be of principal importance (see also Medvedev’s report in Sept. meeting) IMAGE session, Naka, October 2007
Nonlinear 3D MHD CodeNFTC • Simulates NTM evolution in ITER inductive scenario • Simulates seed island formation from sawtooth • Predicts double threshold. Needs clarification, benchmarking with XTOR IMAGE session, Naka, October 2007
2007-2008 plans for ITER simulations • Plasma start-up and termination • RWM theory, code development, modeling and control options • FPP – NBI modules, code development for self consistent simulation of the AE excitation and associated FP transport • Reorganization of the codes according to ITER ITM strategy • Detailed description of the physics model and mathematical algorithms employed – key issue for successful benchmarking and mutual progress! IMAGE session, Naka, October 2007