Twin-Screw Extruder and Pellet Accelerator Integration Developments for ITER

Conference · Sat Jan 01 00:00:00 EST 2011

OSTI ID:1056902

Meitner, Steven J ^[1]; Baylor, Larry R ^[1]; Combs, Stephen Kirk ^[1]; Fehling, Dan T ^[1]; Foust, Charles R ^[1]; McGill, James M ^[1]; Rasmussen, David A ^[1]; Maruyama, So ^[2]

---

1. ORNL
2. ITER Organization, Cadarache, France

The ITER pellet injection system consisting of a twinscrew frozen hydrogen isotope extruder, coupled to a combination solenoid actuated pellet cutter and pneumatic pellet accelerator, is under development at the Oak Ridge National Laboratory. A prototype extruder has been built to produce a continuous solid deuterium extrusion and will be integrated with a secondary section, where pellets are cut, chambered, and launched with a single-stage pneumatic accelerator into the plasma through a guide tube. This integrated pellet injection system is designed to provide 5 mm fueling pellets, injected at a rate up to 10 Hz, or 3 mm edge localized mode (ELM) triggering pellets, injected at higher rates up to 20 Hz. The pellet cutter, chamber mechanism, and the solenoid operated pneumatic valve for the accelerator are optimized to provide pellet velocities between 200-300 m/s to ensure high pellet survivability while traversing the inner wall fueling guide tubes, and outer wall ELMpacing guide tubes. This paper outlines the current twin-screwextruder design, pellet accelerator design, and the integrationrequired for both fueling and ELM pacing pellets.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• DOE Contract Number: DE-AC05-00OR22725
• OSTI ID: 1056902
• Resource Relation: Conference: 38th International Conference on Plasma Science and 24th Symposium on Fusion Engineering (SOFE), Chicago, IL, USA, 20110626, 20110630
• Country of Publication: United States
• Language: English