The subject is estimation of the maximum values of the heat flux at steady-state nominal operating conditions in the reactor BR2. A strong variation of the fuel depletion and the heat flux with the azimuthal direction and dependence on the orientation of the fuel element in the core are obtained. The full-scale 3-Dimensional MCNP&ORIGEN-S heterogeneous geometry model of BR2 with detailed 3-D isotopic fuel depletion profile, including a detailed azimuth fuel modeling, is developed. The relative azimuth power distribution is calculated with MCNP and introduced into ORIGEN-S to evaluate the azimuth isotopic fuel profile. The applied detailed azimuth fuel modeling is compared with homogeneous one in the hot plane. An increase of the maximum heat flux value of 5% for low burnt fuel and 20% for highly burnt fuel due to the azimuth fuel modeling is obtained. A strong variation of the heat flux with the orientation of the fuel element in the core, modeled with azimuthal fuel profile is observed. Perturbation effects in the maximum heat flux values of 10% for a low burnt fuel and ~ 40% for highly burnt fuel, correlated to different orientations of the fuel element in the core are obtained.