1 / 19

ELMs / LLD

ELMs / LLD. Standard Fiducial. Comparison: LITER, Aerosol and No Lithium Shots No Li 700 mg LITER 7 mg Early Li Aerosol. b N. NeL. CII. I P. W MHD. P RAD. t MHD. P NBI. MHD. I OH. D a. Int. Induct. Comparison: Zeff(0) from Metals

wallis
Download Presentation

ELMs / LLD

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. ELMs / LLD Standard Fiducial

  2. Comparison: LITER, Aerosol and No Lithium Shots No Li 700 mg LITER7 mg Early Li Aerosol bN NeL CII IP WMHD PRAD tMHD PNBI MHD IOH Da Int. Induct.

  3. Comparison: Zeff(0) from Metals No Li 700 mg LITER7mg Early Li Aerosol Estimated Contribution of Metals to Zeff 0.6 LITER 0.4 Dimensionless 0.2 Aerosol Injection No Li 0 0 0.2 0.4 0.6 0.8 Time (sec) S. Paul

  4. Goal(s) of the XP • Establish whether or not the 1st aerosol experiment was a fluke. • Fiducials: H mode by early NBI overdrive - no CS gas • Early aerosol injection – before L-to-H transition • 10 mg/s and higher – probe the limit of Li aerosol mass flux • Push plasma performance • If problems try OH shot or two • -------------------------- If time permits ------------------------------------ • 2. Investigate effects on ELMs. • Can aerosol trigger small ELMs at higher flux rates (>35mg/s)? • 3. Investigate whether more Li atoms can be injected than D2 atoms. • LLD loading - need relevant discharge • 4. Investigate Li efficacy with double null discharges

  5. Shot 130388: Early Injection of Li Powder • Nominal aerosol trajectories shown by red vertical lines Plasma Encounters Aerosol Particles X-Point Established (H-mode @ 180 ms) Stored Energy Steady State Li+1Rings Observed (Fig 12) 25 ms 58 ms 80 ms 102 ms 509 ms

  6. 2005 First LSN NBI D Shot After 25 mg of Li Pellet Injection Exhibited Factor ~50% Decrease in Density Lower single-null divertor discharges, 0.45T, D2 gas fueling 3.5mg • 25 mg of Li pumping of edge density saturated after the 3 similar D discharges and returned to pre-Li wall conditions, as expected if most injected gas reacts with the deposited Li. • Rate of density rise is below NBI fueling rate. H. Kugel M. Bell

  7. Camera View of Early Li Aerosol InjectionTaken at t ~ 60 ms

  8. The Subtle Difference Between 130386 and 130389 130386 @ 85 ms No Li 130389 @85 ms Early Powder

  9. Why a Double Null Discharge Would be Interesting Powder Injector Li Ions Head Preferentially for Upper Strike Points

  10. Getting Toward the Center Stack ( or LLD) - Early (Using a “Splash Plate”) ~ 45 Deg Inverted Spoon ~ 45 Deg Flat Plate Present Design Flat Plate LLD

  11. Aerosol Injection 10 mg/s

  12. Aerosol Injection 10 mg/s

  13. Early Powder Injection

  14. Early Li 2 sec shot

  15. Li Has Unique Energy Structure – Easy to Create Li+1 Can We Exploit This to Save Early Volt Secs ? +1 Ionization Energy (eV) +2 +3

More Related