TY - GEN
T1 - Supersonic gas injector for plasma fueling
AU - Soukhanovskii, V. A.
AU - Kugel, H. W.
AU - Kaita, R.
AU - Roquemore, A. L.
AU - Bell, M.
AU - Blanchard, W.
AU - Bush, C.
AU - Gernhardt, R.
AU - Gettelfinger, G.
AU - Gray, T.
AU - Majeski, R.
AU - Menard, J.
AU - Provost, T.
AU - Sichta, P.
AU - Raman, R.
PY - 2006
Y1 - 2006
N2 - A supersonic gas injector (SGI) has been developed for fueling and diagnostic applications on the National Spherical Torus Experiment (NSTX). It is comprised of a graphite converging-diverging Laval nozzle and a commercial piezoelectric gas valve mounted on a movable probe at a low field side midplane port location. Also mounted on the probe is a diagnostic package: a Langmuir probe, two thermocouples and five pick-up coils for measuring toroidal, radial, vertical magnetic field components and magnetic fluctuations at the location of the SGI tip. The SGI flow rate is up to 4 × 1021 particles/s, comparable to conventional NSTX gas injectors. The nozzle operates in a pulsed regime at room temperature and a reservoir gas pressure up to 0.33 MPa. The deuterium jet Mach number of about 4, and the divergence half-angle of 5° - 25° have been measured in laboratory experiments simulating NSTX environment. In initial NSTX experiments reliable operation of the SGI and all mounted diagnostics at distances 1-20 cm from the plasma separatrix has been demonstrated. The SGI has been used for fueling of ohmic and 2-4 MW NBI heated L- and H-mode plasmas. Fueling efficiency in the range 0.1 - 0.3 has been obtained from the plasma electron inventory analysis.
AB - A supersonic gas injector (SGI) has been developed for fueling and diagnostic applications on the National Spherical Torus Experiment (NSTX). It is comprised of a graphite converging-diverging Laval nozzle and a commercial piezoelectric gas valve mounted on a movable probe at a low field side midplane port location. Also mounted on the probe is a diagnostic package: a Langmuir probe, two thermocouples and five pick-up coils for measuring toroidal, radial, vertical magnetic field components and magnetic fluctuations at the location of the SGI tip. The SGI flow rate is up to 4 × 1021 particles/s, comparable to conventional NSTX gas injectors. The nozzle operates in a pulsed regime at room temperature and a reservoir gas pressure up to 0.33 MPa. The deuterium jet Mach number of about 4, and the divergence half-angle of 5° - 25° have been measured in laboratory experiments simulating NSTX environment. In initial NSTX experiments reliable operation of the SGI and all mounted diagnostics at distances 1-20 cm from the plasma separatrix has been demonstrated. The SGI has been used for fueling of ohmic and 2-4 MW NBI heated L- and H-mode plasmas. Fueling efficiency in the range 0.1 - 0.3 has been obtained from the plasma electron inventory analysis.
UR - https://www.scopus.com/pages/publications/34547805644
UR - https://www.scopus.com/pages/publications/34547805644#tab=citedBy
U2 - 10.1109/FUSION.2005.252925
DO - 10.1109/FUSION.2005.252925
M3 - Conference contribution
AN - SCOPUS:34547805644
SN - 142440150X
SN - 9781424401505
T3 - Proceedings - Symposium on Fusion Engineering
BT - 21st IEEE/NPS Symposium on Fusion Engineering, SOFE'05
T2 - 21st IEEE/NPS Symposium on Fusion Engineering, SOFE'05
Y2 - 26 September 2005 through 29 September 2005
ER -