Growth of the tearing mode: Boundary and scaling effects

Journal Article · Sat Jan 01 04:00:00 EST 1983 · Phys. Fluids; (United States)

DOI:https://doi.org/10.1063/1.864000· OSTI ID:6788955

Steinolfson, R S; Van Hoven, G

The linear development of the resistive tearing instability in a sheet pinch is investigated numerically. Particular emphasis is placed on effects which differentiate magnetic tearing in astrophysical situations from that in laboratory devices. These include extreme values of the parameters determining the mode growth and a variety of boundary conditions. Eigenfunction profiles for long and short wavelengths are computed and the applicability of the ''constant Psi'' approximation is investigated. Nearby conducting walls tend to validate this condition and reduce the growth rate, especially for the long wavelength modes which, otherwise, disturb a larger region of the plasma than do short wavelength modes. Finally, the growth rate p is computed for values of the magnetic Reynolds number S up to 10/sup 12/ and of the dimensionless wavelength parameter ..cap alpha.. down to 10/sup -3/. The results demonstrate, without approximation, the S/sup 2/5/ scaling of p at large ..cap alpha.. (constant Psi) and the S/sup 2/3/ scaling at small ..cap alpha.. (nonconstant-Psi). The ..cap alpha.. and S variation of the growth maximum, which would provide the dominant excitation in the absence of nearby boundaries, is specified for both single- and multiple-tearing layers. The growth maximum is shown to occur in a parametric regime where the constant Psi approximation is not valid.

• Research Organization: Department of Physics, University of California, Irvine, California 92717
• OSTI ID: 6788955
• Journal Information: Phys. Fluids; (United States), Journal Name: Phys. Fluids; (United States) Vol. 26:1; ISSN PFLDA
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700107* -- Fusion Energy-- Plasma Research-- Instabilities
BOUNDARY CONDITIONS
EARTH ATMOSPHERE
EIGENFUNCTIONS
FUNCTIONS
INSTABILITY
INSTABILITY GROWTH RATES
MAGNETOSPHERE
NUMERICAL SOLUTION
OSCILLATION MODES
PINCH DEVICES
PLASMA INSTABILITY
PLASMA MACROINSTABILITIES
PLASMA SHEET
REYNOLDS NUMBER
SCALING LAWS
TEARING INSTABILITY
THERMONUCLEAR DEVICES
TIME DEPENDENCE