Title :
Theoretical modelling of a gas-puff Z-pinch experiment
Author :
Peter, W. ; Davara, G. ; Gregorian, L. ; Velikovich, A. ; Fisher, V. ; Ralchenko, Yu. ; Maron, Yitzhak
Author_Institution :
Dept. of Phys., Weizmann Inst. of Sci., Rehovot, Israel
Abstract :
Summary form only given, as follows. We present theoretical and computational results of the modelling of the CO/sub 2/ gas-puff Z-pinch experiment at the Weizmann Institute of Science. Experimental data of the motion of the plasma column (pinch radius vs. time) were taken from a visible light framing camera and are in excellent agreement with a zero-dimensional slug model. The pinch velocity vs. time was determined from time-resolved Doppler shift measurements of the spectral lines emitted by ions of all charge states. Agreement is very good, until deviations occur at late implosion times. Experimental measurements of electron temperature vs. radius are in agreement with a theoretical model including thermal conduction and Joule heating. A one-dimensional Lagrangian fluid code has been developed to model the collapse. We have developed the capability to analyze line emissions from atoms and ions which account for collisional excitation, de-excitation, ionization (including removal of a few electrons by one impact, and ionization into excited states), three-body, radiative, and dielectronic recombination, spontaneous and induced radiative transitions, and self-absorption into surrounding plasma. Our atomic physics codes allow for modelling of non-Maxwellian electron energy distributions, as is required for these studies. The kinetic algorithms are coupled with our 1-D fluid code in order to model the final implosion phase of the plasma, energy flow in the system, and the plasma transport properties.
Keywords :
Doppler measurement; Doppler shift; Z pinch; explosions; plasma collision processes; plasma diagnostics; plasma heating; plasma kinetic theory; plasma temperature; plasma transport processes; temperature; CO/sub 2/ gas-puff; Joule heating; charge states; collisional deexcitation; collisional excitation; dielectronic recombination; electron temperature; energy flow; gas-puff Z-pinch experiment; implosions; induced radiative transitions; ionization; line emissions; one-dimensional Lagrangian fluid code; pinch radius; pinch velocity; plasma column; radiative recombination; spectral lines; spontaneous radiative transitions; thermal conduction; time-resolved Doppler shift measurements; transport processes; visible light framing camera; zero-dimensional slug model; Atomic measurements; Cameras; Current measurement; Doppler shift; Electrons; Ionization; Plasma measurements; Plasma properties; Plasma transport processes; Temperature measurement;
Conference_Titel :
Plasma Science, 1995. IEEE Conference Record - Abstracts., 1995 IEEE International Conference on
Conference_Location :
Madison, WI, USA
Print_ISBN :
0-7803-2669-5
DOI :
10.1109/PLASMA.1995.533260