隨著都市建築逐漸朝高層與大跨徑結構發展，風對於建築物之影響日益顯著，特別是在高風區或特殊幾何形狀條件下，風致振動可能引發結構共振，進而影響其安全性與舒適性。本研究旨在探討高層建築與橋梁斷面之氣動力行為，並運用計算流體力學(Computational Fluid Dynamics, CFD)模擬技術與風洞實驗進行對照分析，以驗證數值模擬之準確性與可行性。研究首先針對矩形斷面進行二維層流與紊流模擬，並探討不同計算域、加密區域與邊界條件設定對模擬結果之影響。接續進行三維矩形剛性矩形斷面模擬，並與風洞實驗結果進行比對，探討其流場變化與風力係數趨勢之吻合度。最後則是運用二維去模擬各種不同橋斷面的氣動力行為。
結果顯示，CFD模擬可有效捕捉旋渦結構、尾跡發展與風力震盪行為，並能合理預測升力與阻力係數的主趨勢。雖在二維橋樑斷面數值模擬與風洞結果在某些定量結果上存有誤差，特別是在升力係數之預測方面，但整體趨勢一致，驗證了數值方法在早期設計階段之應用潛力。綜合分析可知，透過適當之計算域設計與邊界條件控制，CFD 模擬有助於補足風洞試驗所受之縮尺限制，為未來風敏感結構之氣動力設計與安全評估提供可靠輔助工具。

This study investigates the aerodynamic behavior of high-rise buildings and bridge deck sections by combining Computational Fluid Dynamics (CFD) simulations with wind tunnel experiments. With the increasing prevalence of wind-sensitive structures in modern urban environments, accurately capturing wind-induced forces has become a critical aspect of ensuring structural safety and serviceability. Traditional wind tunnel testing remains a fundamental tool in wind engineering but faces limitations such as high cost, scale effects, and limited flexibility for parametric studies. In contrast, CFD offers a powerful numerical approach that allows full-scale simulations, visualization of complex flow phenomena, and sensitivity analyses under various geometric and environmental conditions.
The research is structured around a multi-stage investigation. Initially, two-dimensional simulations under both laminar and turbulent conditions are conducted on simplified rectangular sections to explore fundamental aerodynamic mechanisms and validate mesh and domain settings. These are followed by three-dimensional simulations of rigid models that mirror wind tunnel conditions, enabling direct comparison and verification. Finally, two-dimensional CFD studies are carried out on various bridge deck geometries to examine the impact of cross-sectional shape on vortex shedding and aerodynamic force coefficients.
The results demonstrate that CFD is capable of effectively capturing essential flow characteristics, including vortex shedding, flow separation, and wake development. Although discrepancies remain in the quantitative prediction of certain force components, the overall agreement with wind tunnel data highlights the method's robustness. This study affirms the value of CFD as a complementary tool for early-stage aerodynamic design, particularly when physical testing is limited or infeasible, and lays a foundation for more advanced simulations involving aeroelasticity and fluid–structure interaction in future research.

[1] Menter, F. R. (1994). “Two-equation eddy-viscosity turbulence models for engineering applications.” AIAA Journal, 32(8), 1598–1605.
[2] Chowdhury, M. I. U. (2017). “CFD analysis of 2D unsteady flow around a square cylinder.”
[3] Bhattacharjee, B., & Dou, H.-S. (2021). “Numerical analysis for 2D flow over different ratio’s rectangular.”, Suranaree Journal of Science and Technology, 28(1),010031(1-9).
[4] 陳敬函（2018）。「高樓建築柔性氣彈模型振動台試驗與風洞試驗之參數識別」，碩士論文，國立成功大學土木工程研究所。
[5] 粘浩（2018）。「風引致結構共振：數值模擬與風動實驗」，碩士論文，國立成功大學土木工程研究所。
[6] 蔡明樹、賴子晴（2024）。「高層建築受風反應之擾動特性風洞試驗研究」，發表於《第十七屆結構工程暨第七屆地震工程研討會》，臺中市，臺灣。
[7] 方富民、陳振華（2012）。「以斷面模型試驗評估長跨度橋梁抗風性能之研究」，內政部建築研究所委託研究報告。
[8] 方富民、陳振華（2013）。「各式橋梁斷面模型氣動力穩定資料庫分析研究」，內政部建築研究所委託研究報告。
[9] 吳唐綺（2017）。「以CFD模擬二維斷面橋體氣動力特性研究」，碩士論文，淡江大學土木工程學系。
[10] 陳政謙（2020）。「基於SST k-ω模型之二維橋樑斷面氣彈力模型特性模擬」，碩士論文，淡江大學土木工程學系。
[11] 張承翰（2024）。「橋梁斷面氣動力行為數值模擬與驗證」，碩士論文，國立成功大學土木工程研究所。
[12] Kutateladze, S. S. and Leontiev, A. I. (1990) Heat Transfer, Mass Transfer and Turbulent Boundary Layers, Hemisphere Publishing Corporation, New York, Washington, Philadelphia, London.
[13] https://zh.wikipedia.org/zh-tw/%E5%8D%A1%E9%97%A8%E6%B6%A1%E8%A1%97 ， 訪問時間：2025.05.23。
[14] D.Sumner (2013). “Flow above the free end of a surface-mounted finite-height circular cylinder: A review”, Journal of Fluids and Structures, Volume 43, pp. 41-63
[15] Haym Benaroya, Rene D Gabbai (2008) “Modelling vortex-induced fluid–structure interaction”, Theme Issue ‘Experimental nonlinear dynamics II. Fluids’,158 Volume 366, issue 1868.
[16] 朱佳仁(2006)。「風工程概論」，台北，科技圖書股份有限公司。
[17] 方中(2021)。「基礎流體力學」，台中，滄海書局。
[18] 虎門科技，ANSYS訓練課程，上課教材及操作手冊(2024)。
[19] ANSYS Inc. (2024). “Ansys Fluent theory guide (Release 2024 R2)”. ANSYS Inc. https://www.ansys.com
[20] B. E. Launder and D. B. Spalding. (1974) "The Numerical Computation of Turbulent Flows". Computer Methods in Applied Mechanics and Engineering. 3. 269-289.
[21] D. C.Wilcox(1998). Turbulence Modeling for CFD. DCW Industries, Inc. La Canada, California.
[22] 成功大學航太科技研究中心風洞實驗室（2023）。「橋梁斷面風洞試驗報告：興中路底跨基隆河連接內湖復育園區新設自行車橋興建工程之橋梁風洞試驗」。委託單位：恆康工程顧問股份有限公司。
[23] Liao, Q. Y., Kang, C. J., Wu, C. C., Chu, S. Y., Fang, C., Chung, C. Y., & Chou, C. C. (2025). A comparative assessment of modal parameters and flutter derivatives using multiple output-only system identification methods. Wind and Structures, 40(4), 221–235.
[24] https://blog.csdn.net/a5567899/article/details/137195296 ， 訪問時間：2025.06.23。
[25]Loviconi Ilyas. (2024). Computational fluid dynamics and large eddy simulations: Engineer internship report. Vibration Monitoring and Control Laboratory, National Cheng Kung University.
[26]Pope, S. B. (2000). Turbulent flows. Cambridge University Press.
[27]Wilcox, D. C. (2006). Turbulence modeling for CFD (3rd ed.). DCW Industries.