2 and 3-D MHD Calculations Of the plasma Focus and Flow-through Z-pinch

The authors report on 2 and 3-D MHD calculations of the focus and flow-through Z-pinch using TRAC2 and TRAC3 codes and stability calculations using a 3-D, linearized stability code. The effects of rotation can be studied with all the codes. Axisymmetric perturbations in the current sheath velocity at the beginning of pinching in the focus are calculated in TRAC2 to wash out suggesting stabilization against sausage-like modes because of axial flow during pinching. Rotation of a sharp profile stationary Z-pinch is found to reduce the growth rate of the kink instability. Further studies of the stability of rotating, diffuse-profile pinches will be reported. 2-D calculations have established subAlfvenic, diffuse profile flow states which will be analyzed for stability. It is important to have subAlfvenic flow speeds to achieve a high Q fusion reactor system.