Coupled description of plasma transport and plasma-wall processes

A coupled description of plasma transport and plasma-wall processes has been performed for the small research tokamak device UNITOR (R = 0.3 m, a = 0.1 m), whose regime of parameters is relevant for the plasma edge of fusion orientated experiments. For the comparison between experimental and theoretical data, the following measurements were used: Tsub(e), Tsub(i) on axis from combined plasma current, loop voltage and bremsstrahlung measurements in the soft X-ray regime and from Doppler spectroscopy at Hsub(α) and Hsub(β) lines, anti nsub(e) side-on mixrowave interferometry measurements, nsub(H) from laser induced fluorescence spectroscopy using a collisional-radiative model. These data enabled us to get, from our numerical model, information about the diffusion coefficient (Bohm-Pfirsch-Schluter diffusion), the attenuation factor αsub(H) determining the fraction of the outgoing neutral flux interacting with the wall (approx. equal to 0.25) and the ion reflection coefficient (approx. equal to 1, corresponding to total reflection). (orig.)