Pellet injection on the ZT-40M reversed field pinch

Journal Article · Sat Aug 01 04:00:00 EDT 1987 · Rev. Sci. Instrum.; (United States)

DOI:https://doi.org/10.1063/1.1139421· OSTI ID:6459820

Watt, R G; Wurden, G A; Weber, P G; Buechl, K; Spanos, E K

The four barrel pneumatic pellet injector originally used on the Alcator C tokamak at MIT has been reconfigured for use on the ZT-40M reversed field pinch (RFP) at Los Alamos National Laboratory. The lower temperature and density in this device require operation at velocities significantly lower than on Alcator. Allowing a 2-s warmup prior to firing the injector has enabled operation with pressures as low as 40 psig and velocities ranging as low as 200 m/s with H/sub 2/ pellets, without major cryostat modification. Initial injection experiments in the ZT-40M plasma have verified that pellet refueling is effective for density control, but the net particle inventory increase is less than might be expected based on simple models. Indications of nonoptimal penetration and curvature of the pellet trajectory, in addition to comparable time scales for particle confinement and pellet transit, may account for this.

• Research Organization: Los Alamos National Laboratory, Los Alamos, New Mexico 87545
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 6459820
• Journal Information: Rev. Sci. Instrum.; (United States), Journal Name: Rev. Sci. Instrum.; (United States) Vol. 58:8; ISSN RSINA
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700205* -- Fusion Power Plant Technology-- Fuel
Heating
& Injection Systems
COMPUTERIZED CONTROL SYSTEMS
CONFINEMENT
CONFINEMENT TIME
CONTROL SYSTEMS
DESIGN
ELEMENTS
FABRICATION
FUEL PELLETS
HYDROGEN
LASL
MODIFICATIONS
NATIONAL ORGANIZATIONS
NONMETALS
OPERATION
PELLET INJECTION
PELLETS
PLASMA CONFINEMENT
PLASMA DENSITY
US AEC
US DOE
US ERDA
US ORGANIZATIONS
ZT-40 DEVICES