A comprehensive investigation of the three-dimensional flow phenomena within the wire-wrapped 169-pin fuel assembly of the Japanese loop-type sodium-cooled fast reactor MONJU was conducted through numerical analysis using the widely-used commercial computational fluid dynamics code STAR-CCM+. The intricate vertical flow patterns within the wire-wrapped 169-pin fuel assembly were accurately represented through Reynolds-averaged Navier-Stokes flow simulations, including the turbulent stress transport model. The results of the Computational Fluid Dynamics (CFD) analysis exhibit a favorable alignment with the temperature distribution trends when compared to experimental data. Furthermore, a strong correlation between the temperature distribution of the experimental results and the CFD analysis outcomes was observed, indicating the effective reproduction of the observed temperature distribution within the experimental dataset. This underscores the capability of numerical analysis in faithfully replicating the temperature distribution as observed in the experimental data.