Computational investigation of the limits to Pease-Braginskii collapse of a Z-pinch

Thesis/Dissertation · Thu Jan 01 04:00:00 EST 1981

OSTI ID:6934146

Nielsen, P D

This dissertation investigated the one-dimensional limits to such a radiation enhanced collapse through the use of a Lagrangian simulation code, LASNEX. The code includes the effects of a wide range of phenomena-opacity, ionization, experimentally determined equations of state, magnetic effects on transport coefficients, and external electrical circuits. Special attention was given to the magnetic field subroutines. They were revised to include ion acoustic and lower hybrid drift induced resistivity and to increase accuracy and efficiency. The magnetic pressure term was differenced in a manner that eliminates any influence of zone size, allowing large, low density zones outside the plasma column. In these large zones, magnetic flux and energy were determined by direct integration instead of summation to increase overall conservation. With these changes, the computational timesteps were determined by phenomena in the plasma instead of the Alfven velocity in the low density region. These modifications improved the accuracy of the code on Z-pinch problems by a factor of 10 to 100 depending on the minimum pinch radius reached.

• OSTI ID: 6934146
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700105* -- Fusion Energy-- Plasma Research-- Plasma Kinetics-Theoretical-- (-1987)
COMPUTERIZED SIMULATION
CURRENTS
ELECTRIC CURRENTS
EQUILIBRIUM PLASMA
FLUID MECHANICS
HYDRODYNAMICS
LINEAR PINCH DEVICES
LINEAR Z PINCH DEVICES
MAGNETOHYDRODYNAMICS
MECHANICS
ONE-DIMENSIONAL CALCULATIONS
OPEN PLASMA DEVICES
PINCH DEVICES
PLASMA
SIMULATION
THERMONUCLEAR DEVICES