THE DYNAMIC BEHAVIOR OF THE TUBULAR PINCH EFFECT

Journal Article · Thu Jun 01 04:00:00 EDT 1961 · Zeitschrift fuer Naturforschung (West Germany) Divided into Z. Nautrforsch., A, and Z. Naturforsch., B: Anorg. Chem., Org. Chem., Biochem., Biophys.,

OSTI ID:4839491

Lehner, G

In a tubular pinch configuration the plasma cylinder is simultaneously compressed by magnetic fields radially both from the outside and from the inside. This configuration is investigated theoretically and experimentally. For the theoretical model ohmic resistivities are neglected and adiabatic compression is assumed. This theoretical model yields the times of the successive compressions of the plasma. For the experiments a capacitor bank of 40 mu F and 40 kv is used. It is discharged through a vessel of 50 cm length, 10 cm I.D. and 20 cm O.D. at 10/sup -2/ to 10/sup -1/ mm of deuterium. The maximum currents are approximately 700 kamp. The half period is 4.5 mu sec. Measurements of currents are made with Rogowski-coils, of magnetic fluxes with loops and of magnetic fields with probes. The time history of the intensity of a number of spectral lines is recorded. The experimental results are compared with the theory. The experimental times at which compressions occur are found to be 10% larger than the theoretical times. This discrepancy can be eliminated by the proper choice of a factor in the theory. Two oscillatory modes evolve from the linearization of the equations of the adiabatic model. These modes resemble the in and out of phase coupling of two pendulums. Due to the cylinder symmetry of the plasma configuration the in phase oscillation is excited. When the amplitude of this oscillation becomes large enough for the plasma to hit the walls, the appearence of spectral lines of impurities from the walls is observed. The intensities of these impurity-lines first decrease and then increase with increasing stabilizing longitudinal magnetic fields. The minimum of the intensities of the lines is found to lie between 500 and 1000 gauss. The initial decrease of the intensities is interpreted as an increase of the stability of the plasma, while the succeeding increase of intensities is interpreted as a consequence of the in phase oscillation. (auth)

• Research Organization: Institut fur Plasmaphysik, Munich
• NSA Number: NSA-15-031743
• OSTI ID: 4839491
• Journal Information: Zeitschrift fuer Naturforschung (West Germany) Divided into Z. Nautrforsch., A, and Z. Naturforsch., B: Anorg. Chem., Org. Chem., Biochem., Biophys.,, Journal Name: Zeitschrift fuer Naturforschung (West Germany) Divided into Z. Nautrforsch., A, and Z. Naturforsch., B: Anorg. Chem., Org. Chem., Biochem., Biophys., Vol. Vol: 16a; ISSN ZNTFA
• Country of Publication: Country unknown/Code not available
• Language: German

Related Subjects

CAPACITORS
COILS
CONFIGURATION
DEUTERIUM
MAGNETIC FIELDS
OSCILLATIONS
PHYSICS
PINCH
PLASMA
PRESSURE
STABILITY
TUBES
TURBULENCE
VESSELS