19世紀的實驗中，奧地利物理學家暨工程師Von Strouhal首次發現流場中的圓柱產生渦旋溢放現象以來，流體力學在理論推導和工程應用方面的發展，鈍形體表面流場的研究一直是許多學者熱衷的研究課題之一，因為這些研究對於航太、土木、建築、海洋等工程領域都具有重要的應用價值。圓柱流場是一個複雜且經典的流體力學問題，在均勻流體通過圓柱後，觀察到圓柱尾流上下擺盪的渦旋溢放現象，這是尾部渦流上下交互作用導致的週期性變化。渦旋溢放現象在日常生活中也是常見的，例如鋼索橋體的震盪等。近年來，改善渦旋溢放現象一直受到許多研究人員的關注，並且利用開縫圓柱來改善這一現象的研究已有一段時間，然而很少有人探討開縫圓柱中角度對於流場特性的影響。本研究旨在通過改變開縫圓柱的角度，探討其對渦旋溢放現象的影響，透過對開縫圓柱不同角度的研究，研究人員希望瞭解角度對渦旋溢放的控制效果，並找到最佳的角度設計來減少此現象的發生。
通過使用計算流體力學（CFD）模擬研究，可以觀察並分析開縫圓柱在不同角度下的渦旋溢放現象，並評估其對流場行為的影響，其結果將提供寶貴的資訊，有助於優化開縫圓柱的設計，進而改善並提高流體動力性能，並在實際工程中應用。

In the 19th century, Austrian physicist and engineer Von Strouhal made the first discovery of vortex shedding phenomenon in the flow field around a circular cylinder. Since then, the development of fluid mechanics in its theoretical deduction and engineering applications has shown significant growth. The study of flow fields around blunt bodies has been a popular research topic among many scholars, as it holds crucial application value in aerospace, civil engineering, construction, marine engineering, and other engineering fields. The flow field of a circular cylinder is a complex and classic problem in fluid mechanics, where, after the flow of a uniform fluid past the cylinder, oscillating vortex shedding phenomenon is observed, resulting from the periodic interaction of vortices at the rear of the cylinder.
Vortex shedding phenomena are also commonly observed in everyday life, such as the vibrations of steel cable bridges. In recent years, improving vortex shedding phenomenon has garnered much attention from researchers, and the study of using slotted cylinders to mitigate this phenomenon has been ongoing for some time. However, few researchers have explored the influence of the angle of the slotted cylinder on its flow field characteristics. This research aims to investigate the effects of changes in the angle of the slotted cylinder on vortex shedding phenomena. Through studying slotted cylinders at different angles, researchers hope to understand the control effects of angle variation on vortex shedding and identify the optimal angle design to minimize the occurrence of this phenomenon.
Using Computational Fluid Dynamics (CFD) simulation, the research will observe and analyze the vortex shedding phenomena of slotted cylinders at different angles and evaluate their influence on flow behavior. The results will provide valuable information for optimizing slotted cylinder designs, thereby improving, and enhancing fluid dynamics performance, and facilitating practical engineering applications.

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