Numerical study of drift-kinetic evolution of collisional plasmas in tori

Preliminary numerical results for the dynamics of toroidally confined plasmas in the drift-kinetic, Fokker-Planck description are discussed. These solutions were obtained by using the collisional plasma model (CPM). An initial value problem was solved in which collisions and particle dynamics compete in a given magnetic field to set up a quasi-equilibrium. The plasma (guiding center) distribution function and many macroscopic quantities of interest are monitored. Good agreement with corresponding but more approximate theories is obtained over a wide range of collisionality, particularly with regard to the neoclassical particle flux. Confirmation of earlier results for the distribution function is achieved when due account is taken of the differing collisionality of particles with differing energies.