Study of the Current Sheath Velocity in a 2.2 kJ Plasma Focus Device

Abstract

In this article, after a brief introduction of MTPF-1 plasma focus device, some of the related experimental data are presented. These data show that it is possible to select the proper gas pressure and discharge voltage in order to have a specified pinch time interval. In addition, the effects of gas pressure and discharge voltage on the current sheath’s mean velocity have also been studied. This study showed that, in the case of argon, the maximum value of the current sheath’s mean velocity is about 5 cm/µs, where it can be obtained under various combinations of the pressures and discharge voltages. By using the speed factor concept, the velocity of the current sheath at the pinch time was also examined. It was determined that in two separate experiments with different gas pressures and discharge voltages, the equality of the pinch times means the approximate equality of the current sheath radial velocities.

Keywords

• plasma focus
• pinch time
• current sheath
• speed factor