1 / 8

Status and proposals of IEA-LT/ITPA collaboration Multi-machine Experiments

Status and proposals of IEA-LT/ITPA collaboration Multi-machine Experiments. Presented by N. Asakura, ITPA SOL and Divertor physics topical group and Collaborators The Second IEA Large Tokamak Workshop, Naka, 23-24, Nov. 2003. Contents: Report on DSOL#1-6 and one new proposal.

tucker
Télécharger la présentation

Status and proposals of IEA-LT/ITPA collaboration Multi-machine Experiments

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Status and proposals of IEA-LT/ITPA collaboration Multi-machine Experiments Presented by N. Asakura, ITPA SOL and Divertor physics topical group and Collaborators The Second IEA Large Tokamak Workshop, Naka, 23-24, Nov. 2003 Contents: Report on DSOL#1-6 and one new proposal IEA/ITPA meeting Naka Nov. 23, 2003

  2. DSOL-1: Scaling of Type-1 ELM energy loss • Goal: To better predict divertor and first-wall heat loads during ELMs • Areas of concentration • ELM divertor heat pulse profile, deposition time and amount • Processes whereby core heat/particles are transferred to SOL • Characterization of radial transport of ELM energy • Collaborators: A. Loarte, T. Leonard, N. Asakura, W. Suttrop, G. Counsell, A. Herrmann • Results (2003) • JET/Fundamenski measurement of ELM radial velocity/energy falloff • ASDEX Upgrade measurement of far SOL ELM m/n number • JET - DIII-D dimensionless comparison (r* scaling)& AUG (in pedestal group) • Plans (2004) • Continued measurement and analysis of radial ELM propagation (radial velocity and particle flux at the first wall/in SOL): MAST, AUG, DIII-D, JT-60U, JET • Joint. Exp. Plan: Toroidal and Poloidal distributions of heat flux(AUG:Feb. and MAST:June) • ELM heat and particle measurements may be available in joint experiment plans in pedestal group. IEA/ITPA meeting Naka Nov. 23, 2003

  3. DSOL-2: Tritium codeposition • Goal: To better predict the T inventory • Areas of concentration • Understanding of local and global carbon transport • Understanding of chemical sputtering yield variation among experiments • Development and sharing of new diagnostics (e.g. quartz microbalance) • Effect of mixed materials on T inventory (e.g. W or Mo) • Collaborators: V. Philipps, D. Whyte, G. Federici, P. Coad, P. Ghendrih, V. Rohde, B. Lipschultz, S. Higashijima • Results (2003) • Achievement of global balances of material erosion and deposition (JET, AUG, TEXTOR) • Divertor geometry (strike point location) affects co-deposition (demonstration of QMB in JET) • Plans (2004) • C-13 injection experiments to understand C migration (DIII-D, JET,JT-60U, TEXTOR), and also global transport (see DSOL-6) • Hydrocarbon injection to quantify chemical erosion data (JET, AUG, TEXTOR, JT-60U) IEA/ITPA meeting Naka Nov. 23, 2003

  4. DSOL-3: Scaling of radial transport • Goal: To better predict divertor & first-wall power/particle loadings • Areas of concentration • Develop same measurements techniques for SOL profiles of ne, Te, SIon • Collection of dimensionless similar and dissimilar discharges for analysis • Comparison of inner and outer SOL transport and turbulence • Collaborators: B. Lipschultz, D. Whyte, G. Matthews, R. Pitts, G. Counsell, A. Kallenbach, T. Nakano, N.Asakura • Results (2003) • Obtained dimensionless similar (to C-Mod, DIII-D) discharges on JET • Effective convective velocity veff ~ a0.25 • Plans (2004) • Multi-machine modeling with fluid code under planning/negiciating (Ped. TG) • Expand database from L-mode to H-mode discharges on same tokamaks: Joint Exp. Plan expand database to AUG, NSTX, MAST H-modes. IEA/ITPA meeting Naka Nov. 23, 2003

  5. DSOL-4: Disruptions and effect on materials choices • Goals: • Better characterize divertor/first-wall heat loading • Understand if there are any size effects on the division of power loadings • Evaluate the performance of different materials for divertor/first-wall • Areas of concentration • Comparison of heat deposition time and profile, radiation during thermal quench in multi-machines (over various disruptions: beta-limit, high-density, Locked-mode, etc.). • Collaborators: D. Whyte, G. Matthews, R. Pitts, A. Mahdavi, A. Herrmann, R. Granetz, G.Counsell, V. Riccardo, K.H. Finken • Results (2003) • Broad power deposition profile in the divertor in AUG and JET • Power fraction to divertor: different in JET rather than ASDEX-Upgrade/DIII-D • Analysis of the effect of disruption mitigation on wall materials • Plans (2004) • Continued modelling of how the use of different gases affects the power deposition and thus melting • Disruption mitigation experiments on JET and C-Mod • Comparison of disruptions in ‘similar’ discharges on JET/AUG/DIII-D/MAST IEA/ITPA meeting Naka Nov. 23, 2003

  6. DSOL-5: Role of Lyman absorption in the divertor • Goals: Understand whether Lyman absorption is important to include in fluid models • Areas of concentration • Develop EIRENE to handle radiation transport • Benchmark against C-Mod (opacity due to high density) and JET (opacity due to large size) • Collaborators: D. Reiter, J. Terry, G. Matthews • Results (2003) • Implemented pressure (Stark-) broadening • Tested against HID lamps - Stark effect small for ITER • Plans (2004) • Implement isotope effects (line mixing) and and Zeeman splitting • Model radiation transfer in JET and C-Mod (existing data). IEA/ITPA meeting Naka Nov. 23, 2003

  7. DSOL-6: Parallel transport in the SOL • Goal: Capability to predict flow pattern in SOL • Areas of concentration • SOL flows at a number of points (High-&Low-Field-sides, Top, Divertor): Determination of the flow pattern consistent with experiments and simulations? • Determination of influence of the SOL flow pattern on impurity transport • Experiments to determine influence of plasma rotation on parallel flows • Collaborators: N. Asakura, G. Porter, K. Erents, B. LaBombard, J. Neuhauser • Results (2003) • HFS SOL Mach flow meas. (C-Mod) - large flows to HFS divertor (also in JT-60U) • Doppler measurements (C-Mod, several locations) being compared to Mach probes • Puff & Pump affects the SOL flow and particle flux at HFS more than LFS (JT-60U) • Plans (2004) • Continued Mach probe/Doppler comparisons (C-MOD) • Comparison with Experiments and Simulations with drifts, and Influence of the SOL flow (fast flow/ flow reversal) on the impurity transport/shielding is also determined (JT-60U, DIII-D, JET, C-MOD/ UEDGE-code) . • C-13 injection of global impurity transport (DIII-D, JET, JT-60U, ASDEX-U) IEA/ITPA meeting Naka Nov. 23, 2003

  8. New proposal - Multi-machine study on separatrix density and edge density profiles • Goal: Proper prediction of the separatrix density and its gradient important for controlling particle exhaust and fueling in H-mode • Areas of concentration • ne & Te measurements of the completer profile from pedestal to wall • ne/nsep and fraction of the pedestal inside separatrix • Collaborators: A. Kallenbach, G. Porter, K. Erents, D. Mossessian, N. Asakura, G. Counsell • Status (2003) • Data collected from AUG, C-Mod, DIII-D, JET, JT-60U and MAST • Scalings obtained (will be presented in 2004 PSI). • Plans (2004) • Comparison of data with DIII-D neutral model of pedestal • Scalings of density gradients IEA/ITPA meeting Naka Nov. 23, 2003

More Related