skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Pellet injector research at ORNL

Conference ·
OSTI ID:6400057

Several advanced plasma fueling systems are under development at the Oak Ridge National Laboratory (ORNL) for present and future magnetic confinement devices. These include multishot and repeating pneumatic pellet injectors, centrifuge accelerators, electrothermal guns, a Tritium Proof-of-Principle experiment, and an ultrahigh velocity mass ablation driven accelerator. A new eight-shot pneumatic injector capable of delivering 3.0 mm, 3.5 mm, and 4.0 mm diameter pellets at speeds up to 1500 m/s into a single discharge has been commissioned recently on the Tokamak Fusion Test reactor. The so-called Deuterium Pellet Injector (DPI) is a prototype of a Tritium Pellet Injector (TPI) scheduled for use on TFTR in 1990. Construction of the TPI will be preceded by a test of tritium pellet fabrication and acceleration using a 4 mm bore ''pipe gun'' apparatus. A new repeating pneumatic pellet injector capable of 2.7 mm, 4 mm, and 6 mm operation is being installed on the Joint European Torus to be used in ORNL/JET collaborative pellet injection studies. A 1.5 m centrifuge injector is being developed for application on the Tore Supra experiment in 1988. The new device, which is a 50% upgrade of the prototype centrifuge used on D-III, features a pellet feed mechanism capable of producing variable-size pellets (1.5 to 3.0 mm diameter) optimally shaped to survive acceleration stresses. Accelerating pellets to velocities in excess of 2 km/s is being pursued through two new development undertakings. A hydrogen plasma electrothermal gun is operational at 2 km/s with 10 mg hydrogen pellets; this facility has recently been equipped with a pulsed power supply capable of delivering 1.7 kJ millisecond pulses to low impedence arc loads.

Research Organization:
Oak Ridge National Lab., TN (USA)
DOE Contract Number:
AC05-84OR21400
OSTI ID:
6400057
Report Number(s):
CONF-870629-1; ON: DE87010402
Resource Relation:
Conference: 14. European conference on controlled fusion and plasma physics, Madrid, Spain, 22 Jun 1987; Other Information: Portions of this document are illegible in microfiche products
Country of Publication:
United States
Language:
English