Goktepeli, I.2025-05-112025-05-1120251671-94331993-5048https://doi.org/10.1007/s11804-025-00663-yFlow characteristics around a wall-mounted square cylinder have been numerically simulated at aspect ratios (AR) ranging from 4 to 7 at Re = 10 000. Four turbulence models have been compared in terms of drag coefficient (CD). The closest result has been provided by two turbulence models, namely, k − ε Realizable and k − ω Shear Stress Transport (SST). Hence, these models were utilized to present the flow patterns of pressure distributions, turbulent kinetic energy values, velocity magnitude values with streamlines, streamwise velocity components, cross-stream velocity components and spanwise velocity components on different planes. Flow stagnation has been attained in front of the cylinder. Pressure values peaked for the upstream region. Over the cylinders, the tip vortex structure was dominant owing to the influence of the free end. Flow separation from the top front edge of the body has been obtained. The dividing streamline affected by the flow separation was highly effective in the wake region and moved nearer to the body when the aspect ratio was decreased; the reason was the wake shrinkage owing to the decreasing aspect ratio. Upwash and downwash have been seen in the cylinder wake. These two models presented similar flow patterns and drag coefficients. These drag coefficients are in good agreement with those in previous studies. © Harbin Engineering University and Springer-Verlag GmbH Germany, part of Springer Nature 2025.eninfo:eu-repo/semantics/closedAccessAspect RatioDrag CoefficientReynolds NumberTurbulence ModelWall-Mounted Square CylinderArticle10.1007/s11804-025-00663-y2-s2.0-105003955637