Application of adaptive gridding to magnetohydrodynamic flows

Conference · Tue Dec 31 04:00:00 EST 1996

OSTI ID:489381

Schnack, D D; Lotatti, I; Satyanarayana, P ^[1]

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1. Science Applications International Corp., San Diego, CA (United States)

The numerical simulation of the primitive, three-dimensional, time-dependent, resistive MHD equations on an unstructured, adaptive poloidal mesh using the TRIM code has been reported previously. The toroidal coordinate is approximated pseudo-spectrally with finite Fourier series and Fast-Fourier Transforms. The finite-volume algorithm preserves the magnetic field as solenoidal to round-off error, and also conserves mass, energy, and magnetic flux exactly. A semi-implicit method is used to allow for large time steps on the unstructured mesh. This is important for tokamak calculations where the relevant time scale is determined by the poloidal Alfven time. This also allows the viscosity to be treated implicitly. A conjugate-gradient method with pre-conditioning is used for matrix inversion. Applications to the growth and saturation of ideal instabilities in several toroidal fusion systems has been demonstrated. Recently we have concentrated on the details of the mesh adaption algorithm used in TRIM. We present several two-dimensional results relating to the use of grid adaptivity to track the evolution of hydrodynamic and MHD structures. Examples of plasma guns, opening switches, and supersonic flow over a magnetized sphere are presented. Issues relating to mesh adaption criteria are discussed.

• DOE Contract Number: FG03-91ER54124
• OSTI ID: 489381
• Report Number(s): CONF-960354--
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
99 GENERAL AND MISCELLANEOUS
MAGNETOHYDRODYNAMICS
MESH GENERATION
NUMERICAL SOLUTION
PLASMA FLUID EQUATIONS
PLASMA INSTABILITY
TOKAMAK DEVICES