XMP49:Assessment of TESPEL penetration in

NSTX

N. Tamura, H. Funaba, K. Sato, S. Sudo, NIFSK. Tritz, D. Stutman, L. F. Delgado-Aparicio,

M. Finkental, JHUH. Kugel, R. Kaita, L. Roquemore, M. Bell, PPPL

V. Soukhanovskii, LLNL

NT - 2007 NSTX RR, Jul. 23th-24th, 2007

Goals & Achievements

2/

Goals

Assess TESPEL penetration and its perturbative effects on NSTX plasmas, allowing for future dedicated studies of impurity/heat transport

Achivements

LiH-TESPEL type-D has been successfully injected into NSTX plasmas in collaboration with PPPL and JHU again

A larger TESPEL (1.0 mm, 1.5 mm) can penetrate intoa high-power(6MW) and density H-mode NSTX plasmas

1.0 mm TESPEL penetrates to the core

Experimental Apparatus on NSTX

3/NT - 2007 NSTX RR, Jul. 23th-24th, 2007

In order to inject a TESPEL into a NSTX plasma, a existing Lithium Pellet Injector (LPI) has been used.

Cartridge (sabot, see below) style injector

TESPEL has been loaded intoa sabot (I.D. ~ 2.0 mm)

10 – 200 m/s radial injection

TESPEL for NSTX plasmas consists of deuterated polystyrene (CD) as a shell of that and LiH as a tracer.

LPI

Load port

pellet monitorport

1.0mm TESPEL injection into 6MW H-mode NSTX plasma

4/NT - 2007 NSTX RR, Jul. 23th-24th, 2007

Pellet ablation monitor signals indicates a local deposition of LiH tracer in the TESPEL Clear indication of the

injected TESPEL is observed

Impact of 1.0mm TESPEL injection on profiles of ne and Te in 6MW H-mode NSTX plasma

5/NT - 2007 NSTX RR, Jul. 23th-24th, 2007

0.415 s0.432 s0.448 s0.465 s

0.415 s0.432 s0.448 s0.465 s

At t = 0.448 s (about 2ms after the TESPEL injection), Edge ne is increased, meanwhile core ne is not Core Te is decreasedThis indicates that cold pulse propagates from the edge to the core

1.0mm TESPEL penetration into the 6MW H-mode plasmais also confirmed by a fast camera data

6/NT - 2007 NSTX RR, Jul. 23th-24th, 2007

#119664 0.5mm TESPEL,t = 0.453889 ~ 0.455889 s,duration = 2.111 ms,t ~ 111.11 s

#122952 1.0mm TESPEL,t = 0.452519 ~ 0.455284 s,duration = 2.790 ms,t ~ 24.69 s

Summary & Future plans

7/NT - 2007 NSTX RR, Jul. 23th-24th, 2007

Summary

LiH-TESPEL type-D has been successfully injected into NSTX plasmas in collaboration with PPPL and JHU again

A larger TESPEL (1.0 mm, 1.5 mm) can penetrate into a high-power(6MW) and density H-mode NSTX plasmas

This is confirmed by various diagnostics, fast cameras, filterscopes, USXR, tOSXR, as well as MPTS, CHERS and tangential bolometer

Future plans

Develop the Z-scaling study of impurity transport in NSTX with TESPEL

“Comparison of impurity/electron heat transport in between helical plasmas and ST plasmas” will be proposed, if possible