Modeling Of Lower Hybrid Current Drive In Self-Consistent Elongated Tokamak Equilibria

A simulation model for current drive by lower hybrid slow waves has been generalized to accommodate elongated plasma cross-sections. Toroidal ray trajectories are computed from the magnetic field, density and temperature distributions obtained from a numerical, free boundary solution of the Grad-Shafranov equation. A numerical solution of a relativistic Fokker-Planck equation is used to compute the absorbed power and the driven current. This lower hybrid model has been incorporated into the ACCOME code which iterates between solutions of the Grad-Shafranov equation and computation of the driven current until a self-consistent solution is obtained. Current driven by neutral beams, neoclassical effects and an Ohmic electric field in addition to lower hybrid waves is included. The model is applied to the proposed ITER design under steady state, non-inductive operation.