Stability of tearing modes in tokamak plasmas
The stability properties of m {ge} 2 tearing instabilities in tokamak plasmas are analyzed. A boundary layer theory is used to find asymptotic solutions to the ideal external kink equation which are used to obtain a simple analytic expression for the tearing instability parameter {Delta}{prime}. This calculation generalizes previous work on this topic by considering more general toroidal equilibria (however, toroidal coupling effects are ignored). Constructions of {Delta}{prime} are obtained for plasmas with finite beta and for islands that have nonzero width. A simple heuristic estimate is given for the value of the saturated island width when the instability criterion is violated. A connection is made between the calculation of the asymptotic matching parameter in the finite beta and island width case to the nonlinear analog of the Glasser effect.
- Research Organization:
- Wisconsin Univ., Madison, WI (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- FG02-86ER53218
- OSTI ID:
- 143978
- Report Number(s):
- UW-CPTC--94-1; ON: DE94009205
- Country of Publication:
- United States
- Language:
- English
Similar Records
Mode coupling trigger of neoclassical magnetohydrodynamic tearing modes in tokamaks
Tearing mode analysis in tokamaks, revisited