This work focuses on the investigation of shock/boundary-layer interactions over a three-dimensional half-isolator geometry using Reynolds-Averaged Navier-Stokes (RANS) computations. The results obtained are compared with the experimental work done at North Carolina State University. Previous computational predictions reported in literature had shown differences with the experimental results in the extent of flow separation and pressure rise predicted through the shock/boundary-layer interaction. In order to address these discrepancies, the influence of boundary conditions at the sides on the flow is investigated here. Results show that the use of a subsonic outflow boundary condition along the sides provides closer agreement with the experimental pressure data. Further, unsteady RANS computations are also conducted to investigate potential separation shock unsteadiness and its impact on the extent of flow separation. Finally, to investigate the flow asymmetry observed in the experiments, simulations of flow with deflections of \(1^\circ \) and \(5^\circ \) in the freestream velocity along the azimuth direction are also investigated. The results show that the RANS simulations are able to partially capture the asymmetry reported in the experiments, with the \(5^\circ \) case showing better agreement.