1. No Li 130374 130386 130388 130389 No Li 47 mg 5 mg/s 10 mg/s

5. All eleven shots technically successful – small timing problem Ramp-ups and square wave temporal profiles employed Rates from 1 mg/s to ~ 35 mg/s employed NSTX much more tolerant of Li powder than expected Total of 82 mg injected during 11 shots Not a great day for NSTX reproducibility or documentation 3 - 5 shots have some scientific merit Observed significant decrease in D  and ELMs Timing and location of deposition appeared to be important XP-828 Initial Results and Observations

6. Extra Slides

8. Prototype Acoustic Resonance Dropper Can Drop from 0.3 mg up to Much-Too-Much Powder (Li Surrogate) Velocity at SOL = 4.5 m/sec Powder Injector

9. to Vac Pump 1.0 m 2 ¾ Gate Valve Laser Scattering Module Drop Chamber Bracing ½ O.D. Stainless Tubing Pyrex Tube 2 ½ O.D. Glass Funnel w Long Stem to Vac Pump Existing Computerized Laboratory Test Facility

10. New Umbrella Throttle Seems to Work More Reliably Than Old Simple Throttle Design – Higher Fluxes Simple ThrottleUmbrella Throttle Higher Reliable Particle Flow Li Powder Li Powder (~ 3 mg/s)

11. 0246810121416 0 2 4 8 10 12 14 6 RMS Voltage (Volts) Mass Flux (mg/s) Lithium Particle Flux is an Approximately Linear Function of Resonant Voltage Applied to the Piezoelectric Membrane

12. 01234567 Scattered Laser Signal (A.U.) Time (s) 0.5 V: 0.4 mg/s 1.0 V: 0.7 mg/s 2.0 V: 1.5 mg/s 3.0 V: 2.2 mg/s 8.0 V: 5.8 mg/s Laser Scattered Signal Reproducibility is Fairly Good However, Signal Saturates at 2 - 4 mg/s (3 - 5 Vrms)

13. 0.2 0.40.60.81.00 Time (s) RMS Voltage (Volts) 0 2 4 8 6 Scattered Laser Signal (A.U.) Two Arbitrary Waveforms: Ramp-Ups (4 & 8 Volts Max) Laser Scattered Signal Saturates at 2 - 4 mg/s (3 - 5 Vrms) 6 mg/s 3mg/s

14. 0.2 0.40.60.81.00 Time (s) RMS Voltage (Volts) 0 2 4 8 6 Scattered Laser Signal (A.U.) 6 mg/s Arbitrary Waveform: Ramp-Down (8 Volts Max) Same Laser Scattering Saturation Observed

15. 00.20.40.60.81.01.21.4 RMS Voltage (Volts) 0 4 8 12 Time (s) Scattered Laser Signal (A.U.) 6 mg/s An Arbitary Waveform: With Some Modifications Might “Tweek” ELMS

16. “Early” Li Can be Preferentially Directed to Lower Divertor Pre-Pulse of Lithium for 50 ms (~ 100 Oscillations) 850 ms Before Breakdown Small Plasma Initiated on the Center Stack Flux Plot Shown Just After Breakdown

17. The Two Plasmas to be Used in XP 828 129019129059

18. XP828 Shot No. Dropper mg/s (Max) Temporal Profile Total Lithium (mg) HeGDC (min) Ref #10N/A06 Ref #20N/A06 Ref #30N/A06 13A26 26A66 312A 6 412 or TBDA246 512 or TBDB366 612 or TBDB486 712 or TBDB606 812 or TBDB726 912 or TBDC846 1012 or TBDC966 1112 or TBDC1086 128TBD1166 1310TBD1266 1412TBD1386 1514TBD1526 ------- ---------------

20. Plasma Current Time (sec) Li Flux 01 Pre-programmed Flux Profile Must be Injected ~ 450 ms Before Plasma Breakdown 450 ms

21. 012345678 0 0.01 0.02 0.03 0.04 0.05 0.06 0 NewDiff 1.05FitX_v() 80VoltX_v 

22. 02468101214160 2 4 8 10 12 14 6

23. B T = 0.5 T I p = 800 kA Purpose : Study ELM Suppression by in situ Modification of NSTX Plasma Surface Interaction: Li on Graphite R/a = 1.46 Lower Single Null P NBI = 4 MW Type 1 ELMS Lithium Evaporators with Shutters H. Kugel P2-58 B treated Graphite 2

31. Velocity at SOL = 4.5 m/sec Powder Injector

32. Dropper by Acoustic Resonance Vertical Injection by Acoustic Resonance Horizontal Injection by PZT Fan

33. 100  m Resonating Piezoelectric Disk SLMP Li Powder  Resonant Levitation = ± 0.5 mm ~ 5 lbs

34. 0,1 Mode 290 Hz 0,2 Mode 2 kHz 0,3 Mode Modes of the Vibrating Piezoelectric Drumhead

35. 0,2 Mode of Piezoelectric Disk with Glass Beads – 2 KHz

36. 0,2 Node of Piezoelectric Disk with Glass Beads – 2 KHz

37. 30 mil Scale 20:1 Throttle: ¼ - 28 Screw Piezoelectric Membrane (0,2) Node 3.5 mg/s 0.3 mg/s 100 - 300 mg/s g Fixed Level Inside Node N.B. 30mil Gap: 15 particles high 20 particles wide O-Ring 100 mil

38. Resonating Piezoelectric Disk  Resonant Levitation 25 mm (0,2) Mode Dusting of Glass Spheres Levitated from Center of Mode Throttle used to force Particles to drop through Hole in piezo membrane

39. Dropper by Acoustic Resonance Vertical Injection by Acoustic Resonance Horizontal Injection by PZT Fan (or by Rotating Wheel)