Edge plasma transport modeling for the design of KT-2 tokamak poloidal divertor

A two-dimensional, two-fluid numerical modeling is carried out for the edge plasmas of the KT-2 tokamak with a poloidal divertor configuration. Poloidal drift motions, electrostatic potential and plasma currents are solved self-consistently with other variables in the nonlinear time-dependent transport equations describing particle, momentum and energy conservations for electrons and ions. Transports of recycling neutrals are modeled using the Monte-Carlo simulation. As a result, it is found that the large sheared poloidal rotation exists in the edge region due to the radially-varying electrostatic potential and the resultant radial electric field and that it is mainly driven by an electric (E&oarr;×B&oarr;) drift dominating over a diamagnetic to (∇p_i×B&oarr;) drift. The heat fluxes and sputtering rates are estimated from the present code for the divertor target plates