Preliminary results from the flow-through z-pinch experiments: ZaP

Conference · Thu Jul 01 04:00:00 EDT 1999

OSTI ID:20034264

Shumlak, U; Nelson, B A; Goilingo, R P; Tang, D; Crawford, E; Hartog, D J.D.; Holly, D J

The stabilizing effect of an axial flow on the m = 1 kink instability in z-pinches has been studied numerically by reducing the linearized ideal MHD equations to a one-dimensional eigenvalue equation for the radial displacement. A diffuse z-pinch equilibrium is chosen that is made marginally stable to the m = 0 sausage mode by tailoring the pressure profile. The principal result reveals that a sheared axial flow does stabilize the kink mode when the shear exceeds a threshold value which is inversely proportional to the wavelength of the mode. This threshold value can be satisfied with a peak flow which is less than the Alfven speed for certain wavelengths. Additionally, the m = 0 sausage mode is driven from marginal stability into the stable regime which suggests that the equilibrium pressure profile control can be relaxed. The flow stabilization agrees with experimental observations. The details of the theoretical development will be presented.

• Research Organization: Univ. of Washington, Seattle, WA (US)
• Sponsoring Organization: US Department of Energy
• OSTI ID: 20034264
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
KINK INSTABILITY
LINEAR Z PINCH DEVICES
LONGITUDINAL PINCH
PLASMA DIAGNOSTICS
PLASMA DRIFT
SAUSAGE INSTABILITY
STABILIZATION