The shock/boundary layer interaction experiment performed at IUSTI (Institut Universitaire des Systèmes Thermiques Industriels, Université de Provence) has been computed using the Stimulated Detached Eddy Simulation approach. This computation accounts for the whole wind tunnel span. It suggests that corner separations induced by the presence of lateral walls reduce the effective section of the wind tunnel and strengthen the interaction, making periodic computations irrelevant for strongly separated situations (shock deviation of 9.5 degrees). Furthermore, this computation evidences that the strongest wall pressure fluctuations are found in corner flows. The latter are subjected to low frequency movements which contribute to 30% of the total fluctuations. Nevertheless, it was not possible to connect statistically these movements to the ones of the main separation.