EDGE2D modelling of JET and ITER including the combined effect of guiding centre drifts and an edge transport barrier

Code predictions of parameters in the pedestal region of high power H-mode discharges on JET have been performed using the EDGE2D code including (i) self-physically and chemically sputtered carbon impurities, (ii) guiding centre drifts with realistic core boundary conditions, and (iii) an imposed edge transport barrier (ETB). For a transport barrier with a minimum D ⊥ min < 0.5 m2 s−1 the pedestal (core) carbon content is increased along with the associated radiation by up to 65%, compared with the no drift case. The result is a reduction in pedestal electron temperature and an increase in pedestal density by ∼30%, (such that pressure is unaffected), and inner target detachment. Without drifts, the pedestal pressure, stored energy and energy confinement time increase as ( D ⊥ min ) - 1 / 2 , which is not modified by the inclusion of drifts. Reasonably good agreement with experimental measurements on JET is achieved for a moderate ETB strength of D⊥ = 0.4 m2 s−1. Preliminary results for ITER are discussed.