International Journal of Frontiers in Engineering Technology, 2025, 7(3); doi: 10.25236/IJFET.2025.070313.
Jin Miao, Hongyuan Sun, Dexin Liu
School of Naval Architecture and Port Engineering, Shandong Jiaotong University, Weihai, Shandong Province, 264209, China
Most floating offshore platforms are cylindrical with low aspect ratios, whereas most existing research focuses on structures with high aspect ratios. Research on the influence of the free-end effect on the flow around a cylinder at low aspect ratios is still insufficient. Therefore, in this study, the computational fluid dynamics (CFD) method was used to numerically simulate the flow characteristics of finite and infinite cylinders at different flow rates, and the influence of the free-end effect on the flow characteristics of the cylinders was discussed. The results show that the free-end effect significantly interferes with the flow characteristics of finite cylinders. In particular, for a shorter cylinder (L/D = 2), the free-end effect caused obvious vortex separation and flow instability, resulting in a higher vortex intensity. With an increase in flow velocity, the influence of the free-end effect weakened; however, the flow remained unstable. In contrast, the flow of an infinite cylinder is not affected by the free-end effect and always maintains a stable flow. The vortex region was small, and with the increase in flow velocity, the flow gradually tended to be inertia-dominant, showing more stable flow characteristics.
Flow Around Circular Cylinder; Free-End; CFD; Aspect Ratio; SST k-ω
Jin Miao, Hongyuan Sun, Dexin Liu. Three-Dimensional Numerical Study on the Flow Characteristics of Circular Cylinder Considering the Influence of Free-End. International Journal of Frontiers in Engineering Technology (2025), Vol. 7, Issue 3: 93-100. https://doi.org/10.25236/IJFET.2025.070313.
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