FOM - Institute for Plasma Physics Rijnhuizen Association Euratom-FOM Diagnostics and Control for Burning Plasmas Discussion All of you

Association Euratom-FOM Trilateral Euregio Cluster A.J.H. Donné, W60 Workshop on Burning Plasma Physics and Simulation, Tarragona, 4-5 July 2005 Discussion Where are we? Where do we want to go? How do we get there? Try to define the key issues in the field of control and diagnostics on which further R&D and testing is urgently needed (eg. on present machines)?

Association Euratom-FOM Trilateral Euregio Cluster A.J.H. Donné, W60 Workshop on Burning Plasma Physics and Simulation, Tarragona, 4-5 July 2005 Proposal for discussion points What further steps are needed in dedicated/ integrated plasma control? What are the specific measurement challenges associated with real time control requirements in burning plasmas? What diagnostics do need (or would benefit from) R&D on present devices?

Association Euratom-FOM Trilateral Euregio Cluster A.J.H. Donné, W60 Workshop on Burning Plasma Physics and Simulation, Tarragona, 4-5 July 2005 Key aspects in control – 1/7 Equilibrium control –AC losses –power management –full scenario robustness –development of control matrix for shape and position with minimum coupling between the terms –modeling of breakdown phase

Association Euratom-FOM Trilateral Euregio Cluster A.J.H. Donné, W60 Workshop on Burning Plasma Physics and Simulation, Tarragona, 4-5 July 2005 Key aspects in control – 2a/7 MHD control –Control of NTM’s, sawteeth (yesterdays disc.) Interaction with pellets ECRH stabilization –Control of RWM’s Interaction with pellets RFA extrapolation to ITER? Internal coils needed in ITER What is ‘ideal wall’ in ITER? Coupling to ELMs, NTMs –disruption avoidance and mitigations,

Association Euratom-FOM Trilateral Euregio Cluster A.J.H. Donné, W60 Workshop on Burning Plasma Physics and Simulation, Tarragona, 4-5 July 2005 Key aspects in control – 2b/7 MHD control –ELM control, etc. Pellet ELM triggering Decouple ELM amplitude from pedestal height ELM location (deeper in plasma gives larger ELMs) Extrapolation of ELM-free QH mode to ITER? Control by ergodic fields (pure type II regime?)

Association Euratom-FOM Trilateral Euregio Cluster A.J.H. Donné, W60 Workshop on Burning Plasma Physics and Simulation, Tarragona, 4-5 July 2005 Key aspects in control – 3/7 Current profile control –Development of response matrix –effect of  -heating on current profile Frozen-in-fields (may require ultra-slow fusion power ramp up!) –mode conversion current drive –real-time equilibrium codes incl. bootstrap current and loop voltage profile Bootstrap current driven by fusion power may initiate a current hole

Association Euratom-FOM Trilateral Euregio Cluster A.J.H. Donné, W60 Workshop on Burning Plasma Physics and Simulation, Tarragona, 4-5 July 2005 Key aspects in control – 4/7 Transport barrier control –Identification of key parameters to control ITBs –role with current profile –simulation of ITB control in presence of  - heating –interrelation between ETB and ITB

Association Euratom-FOM Trilateral Euregio Cluster A.J.H. Donné, W60 Workshop on Burning Plasma Physics and Simulation, Tarragona, 4-5 July 2005 Key aspects in control – 5/7 Power control and particle exhaust –Methods for erosion/deposition control –control & monitoring of tritium inventory –edge power dissipation control in ELMy H- mode and ITB scenarios –validation of models of He-ash removal –real-time measurement and control of D/T ratio, –compatibility with good confinement

Association Euratom-FOM Trilateral Euregio Cluster A.J.H. Donné, W60 Workshop on Burning Plasma Physics and Simulation, Tarragona, 4-5 July 2005 Key aspects in control – 6/7 Control of steady state scenarios –Fuelling: how to increase density without destroying barrier (or without perturbing the beneficial pressure profile shape? NBI fuelling rates much lower then present devices HFS injection needed for pellets CT injection? Modeling for ITER. Localization of fuelling. Test on present device (NSTX). –Impurity accumulation and exhaust –disruptivity –develop scenarios with minimum control –control of current and loop voltage under high bootstrap conditions.

Association Euratom-FOM Trilateral Euregio Cluster A.J.H. Donné, W60 Workshop on Burning Plasma Physics and Simulation, Tarragona, 4-5 July 2005 Key aspects in control – 7/7 Other –Integration of all aspects of control (control architectures and methodologies) Based on dynamic models for transients Simulate burning plasma conditions in DT exp. W. ICRH –pre-emptive control (e.g. disruption avoidance), –diagnostic requirements on basis of adequacy for control –use modeling calculations for sensor development, –measurement requirements –indicators for possible loss of  confinement.

Association Euratom-FOM Trilateral Euregio Cluster A.J.H. Donné, W60 Workshop on Burning Plasma Physics and Simulation, Tarragona, 4-5 July 2005 Diagnostic issues Contamination of beam ions in confined alpha diagnostics Development of escaping alpha diagnostics Testing of new – ITER relevant – techniques on present devices FW reflectometer: coupling of antennas into plasma Requirements on fast ions/alphas in velocity space Environmental effects Simultaneous control First mirrors R&D on phenomena, components, techniques

Association Euratom-FOM Trilateral Euregio Cluster A.J.H. Donné, W60 Workshop on Burning Plasma Physics and Simulation, Tarragona, 4-5 July 2005 Specific measurement challenges related to control Impact of the various control issues on the measurement scenarios

Association Euratom-FOM Trilateral Euregio Cluster A.J.H. Donné, W60 Workshop on Burning Plasma Physics and Simulation, Tarragona, 4-5 July 2005 Aims as defined by organizers diagnostic needs and current developments (eg. diagnostics for fast particle thermalisation, re- distribution and loss; neutron yields, fluxes, spectra and tomography; helium ash and helium pumping efficiency; plasma isotopic composition; erosion, redeposition and tritium retention; and other specific diagnostic challenges for burning plasmas); advances in integrated plasma control and dedicated control (eg. of MHD instabilities); specific measurement challenges associated with real time control requirements in burning plasmas (eg. sensors, actuators and modelling for D-T mixture control, burn control, current and pressure control with  - particle driven sources).