Tokamak Plasma Equilibria and Axisymmetric Stability with a Zero Total Toroidal Current
نویسندگان
چکیده
Several tokamak experiments have reported the existence of plasma equilibria with a zero total toroidal current in their AC operations. By taking a plasma profile model based on linear functions of the poloidal flux function ψ , a variety of equilibrium configurations with a zero total toroidal current have been found. The MHD_N0 stability code [1] is able to compute axisymmetric mode stability of nonnested tokamak equilibria with arbitrary island topologies. Both equilibrium and stability codes use the same unstructured triangular grids. The plasma shape and profile effects on the existence and stability of zero total current equilibria were investigated. Stable equilibria against axisymmetric (n=0) ideal MHD modes were discovered with a conducting wall close enough to the plasma boundary.
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