Study on Flow Control Countermeasures of Three-dimensional Cylinder around Offshore Platform

The Karman vortex street problem in fluid coupled with the natural frequency of the bridge structure will resonate and cause damage. Therefore, the phenomenon of Karman vortex street is an important factor that can't be ignored in the building structure, and it must be considered in the construction of offshore platforms with more columns. Mechanics is a very important problem in fluid mechanics. In some cases, when the fluid resistance bypasses an object, the two sides of the object will periodically shed double-row linear vortices with the same arrangement and movement mode, which will lead to the Karman vortex street problem
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. Circular flow is a common way to produce Karman vortex street. Circular flow has important applications in many aspects of engineering, such as ocean engineering. Studying the flow around a cylinder is very important for improving the structural layout of offshore platforms
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. In this paper, the phenomenon of Karman vortex street, which is common in ocean engineering, is explored by CFD method, and the phenomenon of Karman vortex street caused by circular cylinder flow in ocean environment is studied by some projects in ANSYA software, so as to find a model with better vortex suppression effect.