This paper deals with the numerical simulation - made with the self-consistent COREDIV code - of nitrogen seeded JET discharges and with the comparison to the experimental data. The JET discharges we refer to are characterized by q95 = 2.6 (Ip = 3MA), high density (fGW ~1), high radiated fraction (frad ~ 0.8) and moderate confinement (H98 ~ 0.75). Although these JET discharges are type III ELMy H-mode, they lead to a power amplification factor Q in the range 6-10 when scaled to ITER [2] and therefore might be considered as representative in JET of an alternative ITER scenario at higher density, lower confinement and acceptable target load. The main features of the COREDIV code are described in, where it is shown that the code is capable to reproduce satisfactorily the experimental temperature and density profiles as well as the total radiated power, Prad, and the ionic effective charge, Zeff. In this paper we focus on the analysis of some edge properties as the particle fluxes and the compatibility of Zeff with the radiation properties of the impurities.