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完整後設資料紀錄
DC 欄位 | 值 | 語言 |
---|---|---|
dc.contributor.advisor | 朱錦洲(Chin-Chou Chu) | |
dc.contributor.author | Yu-Hao Qiu | en |
dc.contributor.author | 邱榆豪 | zh_TW |
dc.date.accessioned | 2021-06-16T09:26:45Z | - |
dc.date.available | 2025-08-14 | |
dc.date.copyright | 2020-09-10 | |
dc.date.issued | 2020 | |
dc.date.submitted | 2020-08-17 | |
dc.identifier.citation | [1] T. Kawamura, M. Hiwada, T. Hibino, I. Mabuchi, and M. Kumada, 'Flow around a finite circular cylinder on a flat plate: Cylinder height greater than turbulent boundary layer thickness,' Bulletin of JSME, vol. 27, no. 232, pp. 2142-2151, 1984. [2] M. Adaramola, O. Akinlade, D. Sumner, D. Bergstrom, and A. Schenstead, 'Turbulent wake of a finite circular cylinder of small aspect ratio,' Journal of Fluids and Structures, vol. 22, no. 6-7, pp. 919-928, 2006. [3] D. Sumner, 'Flow above the free end of a surface-mounted finite-height circular cylinder: a review,' Journal of Fluids and Structures, vol. 43, pp. 41-63, 2013. [4] J. H. Lienhard, Synopsis of lift, drag, and vortex frequency data for rigid circular cylinders. Technical Extension Service, Washington State University Pullman, WA, 1966. [5] D. J. Tritton, 'Experiments on the flow past a circular cylinder at low Reynolds numbers,' Journal of Fluid Mechanics, vol. 6, no. 4, pp. 547-567, 1959. [6] D. Sucker and H. Brauer, 'Fluiddynamik bei quer angeströmten Zylindern,' Wärme-und Stoffübertragung, vol. 8, no. 3, pp. 149-158, 1975. [7] C. H. Williamson, 'Oblique and parallel modes of vortex shedding in the wake of a circular cylinder at low Reynolds numbers,' Journal of Fluid Mechanics, vol. 206, pp. 579-627, 1989. [8] H. Wang and Y. Zhou, 'The finite-length square cylinder near wake,' Journal of Fluid Mechanics, vol. 638, pp. 453-490, 2009. [9] H. Wang, Y. Zhou, C. Chan, and K. Lam, 'Effect of initial conditions on interaction between a boundary layer and a wall-mounted finite-length-cylinder wake,' Physics of Fluids, vol. 18, no. 6, p. 065106, 2006. [10] H. Wang, Y. Zhou, and J. Mi, 'Effects of aspect ratio on the drag of a wall-mounted finite-length cylinder in subcritical and critical regimes,' Experiments in fluids, vol. 53, no. 2, pp. 423-436, 2012. [11] S. Krajnovic, 'Flow around a tall finite cylinder explored by large eddy simulation,' Journal of Fluid Mechanics, vol. 676, pp. 294-317, 2011. [12] Z. Chen, Z. Hosseini, and R. Martinuzzi, 'The influence of boundary layer state on the wake topology of a surface mounted bluff body,' in Proceedings of 20th Annual Conference of the CFD Society of Canada, CFD, 2012, pp. 9-11. [13] S. Taneda, 'Studies on Wake Vortices (II), Fxperimental Investigation of the Wake Behind Cylinders and Plates at Low Reynolds Numbers,' Res. Inst. Appl. Mech, vol. 1, pp. 29-40, 1952. [14] F. Etzold and H. Fiedler, 'The near-wake structure of a cantilevered cylinder in a cross-flow,' Zeitschrift fur Flugwissenschaften, vol. 24, pp. 77-82, 1976. [15] R. Gould, P. Ponsford, and W. Raymer, Wind tunnel tests on chimneys of circular section at high Reynolds numbers. NPL, 1968. [16] T. Okamoto and M. Yagita, 'The experimental investigation on the flow past a circular cylinder of finite length placed normal to the plane surface in a uniform stream,' Bulletin of JSME, vol. 16, no. 95, pp. 805-814, 1973. [17] T. A. Fox, C. J. Apelt, and G. West, 'The aerodynamic disturbance caused by the free-ends of a circular cylinder immersed in a uniform flow,' Journal of Wind Engineering and Industrial Aerodynamics, vol. 49, no. 1-3, pp. 389-399, 1993. [18] R. Pattenden, S. Turnock, and X. Zhang, 'Measurements of the flow over a low-aspect-ratio cylinder mounted on a ground plane,' Experiments in Fluids, vol. 39, no. 1, pp. 10-21, 2005. [19] T. Tsutsui, 'Flow around a cylindrical structure mounted in a plane turbulent boundary layer,' Journal of wind engineering and industrial aerodynamics, vol. 104, pp. 239-247, 2012. [20] N. Hölscher and H.-J. Niemann, 'Turbulence and separation induced pressure fluctuations on a finite circular cylinder—application of a linear unsteady strip theory,' Journal of wind engineering and industrial aerodynamics, vol. 65, no. 1-3, pp. 335-346, 1996. [21] S. C. Roh and S. O. Park, 'Surface flow pattern and local mass transfer on the free-end surface of a finite circular cylinder,' Heat and mass transfer, vol. 38, no. 1-2, pp. 1-5, 2001. [22] S. Roh and S. Park, 'Vortical flow over the free end surface of a finite circular cylinder mounted on a flat plate,' Experiments in fluids, vol. 34, no. 1, pp. 63-67, 2003. [23] D. Sumner, J. Heseltine, and O. Dansereau, 'Wake structure of a finite circular cylinder of small aspect ratio,' Experiments in Fluids, vol. 37, no. 5, pp. 720-730, 2004. [24] M. Zdravkovich, V. Brand, G. Mathew, and A. Weston, 'Flow past short circular cylinders with two free ends,' Journal of fluid mechanics, vol. 203, pp. 557-575, 1989. [25] W. Gao, D. Nelias, Z. Liu, and Y. Lyu, 'Numerical investigation of flow around one finite circular cylinder with two free ends,' Ocean Engineering, vol. 156, pp. 373-380, 2018. [26] O. Inoue and A. Sakuragi, 'Vortex shedding from a circular cylinder of finite length at low Reynolds numbers,' Physics of Fluids, vol. 20, no. 3, p. 033601, 2008. [27] A. C. Yunus, Fluid Mechanics: Fundamentals And Applications (Si Units). Tata McGraw Hill Education Private Limited, 2010. [28] R. Porteous, D. J. Moreau, and C. J. Doolan, 'A review of flow-induced noise from finite wall-mounted cylinders,' Journal of Fluids and Structures, vol. 51, pp. 240-254, 2014. [29] D. J. Moreau and C. J. Doolan, 'Flow-induced sound of wall-mounted finite length cylinders,' AIAA journal, vol. 51, no. 10, pp. 2493-2502, 2013. [30] C.-W. Park and S.-J. Lee, 'Free end effects on the near wake flow structure behind a finite circular cylinder,' Journal of Wind Engineering and Industrial Aerodynamics, vol. 88, no. 2-3, pp. 231-246, 2000. [31] C.-W. Park and S.-J. Lee, 'Flow structure around a finite circular cylinder embedded in various atmospheric boundary layers,' Fluid Dynamics Research, vol. 30, no. 4, p. 197, 2002. [32] C. Park and S. Lee, 'Effects of free-end corner shape on flow structure around a finite cylinder,' Journal of Fluids and Structures, vol. 19, no. 2, pp. 141-158, 2004. [33] P. Albarède and P. A. Monkewitz, 'A model for the formation of oblique shedding and ‘‘chevron’’patterns in cylinder wakes,' Physics of Fluids A: Fluid Dynamics, vol. 4, no. 4, pp. 744-756, 1992. [34] M. Nishioka and H. Sato, 'Measurements of velocity distributions in the wake of a circular cylinder at low Reynolds numbers,' Journal of Fluid Mechanics, vol. 65, no. 1, pp. 97-112, 1974. [35] C. Mathis, M. Provansal, and L. Boyer, 'The Bénard-von Kármán instability: an experimental study near the threshold,' Journal de Physique Lettres, vol. 45, no. 10, pp. 483-491, 1984. [36] T. Lee and R. Budwig, 'A study of the effect of aspect ratio on vortex shedding behind circular cylinders,' Physics of Fluids A: Fluid Dynamics, vol. 3, no. 2, pp. 309-315, 1991. [37] W. Thielicke and E. Stamhuis, 'PIVlab–towards user-friendly, affordable and accurate digital particle image velocimetry in MATLAB,' Journal of open research software, vol. 2, no. 1, 2014. [38] J. D. Anderson and J. Wendt, Computational fluid dynamics. Springer, 1995. [39] H. Liu, T. Jurkschat, T. Lohner, and K. Stahl, 'Determination of oil distribution and churning power loss of gearboxes by finite volume CFD method,' Tribology International, vol. 109, pp. 346-354, 2017. | |
dc.identifier.uri | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/59528 | - |
dc.description.abstract | 本篇文章架構為以實驗及計算的方式探討低雷諾數流場流體流經有限長度圓柱。 實驗在一個開放式水洞中進行,實驗液體為甘油,而計算模擬的部分使用的軟體為一般商用軟體Ansys Fluent。 Ar(aspect ratio number)的範圍為1.5到6,而雷諾數變化的範圍為Re=10-100我們固定Re探討不同的Ar所造成的影響,固定Ar討論不同Re的變化,在研究了不同Re的變化後,我們發現流況是穩定的且在尾流區域具有雙重對稱性的。 尤其要注意3維流況及橫向於圓柱軸方向之截面,在圓柱尾流區域會有兩種不同形式的流線交織再一起:一種為流體流經圓柱表面向下分離的橫向分流(transverse separation,TS)和從圓柱自由端面分離下來的縱向下沖流(longitudinal separation,LS)。 Ar=4圓柱在Re>50時流況與一般2D圓柱截然不同,在圓柱尾流區域會產生一個奇異點源,與橫向分離流動一起形成一個扭曲的星形圖案,奇異源位於縱向分離所形成的recirculation的中末端,而圓柱與奇異點的距離以d_s表示。 而此奇異點源的強度以SS=-∂v/∂y來表示當Re固定時,d_s隨直徑增加而增加,在Re=10時每根圓柱流況基本一致,隨著Re增加後方尾流區域不斷拉長,而SS在Re=100時當Ar<3後會有明顯的下降,Ar固定時 d_s隨著雷諾數增加而成長,而ss在Re>40後成長為非線性。 | zh_TW |
dc.description.abstract | This article is to report on a joint numerical and experimental investigation of the vortex structures of flow past a circular cylinder of finite span in a range of low Reynolds numbers. The experiments were performed in an open water channel using the glycerol as the working fluid, while numerical simulations were carried out using the commercial code Ansys/Fluent. The aspect ratio Ar of the cylinder varies from 1.5to 6, and the Reynolds number Re varies from 10 to 100. Give a fixed Re we study the various cases of Ar, and given a fixed Ar we study the various cases of Re. In this regime of parameters, the flow is found to be steady, separated and doubly-symmetric. In particular, the 3-dimensional flow streamline pattern as well as its cross sections transverse to the cylinder axis are carefully examined. The streamlines are interweaved by two flow separations: separated flow over the round side of the cylinder (transverse separation, TS) and that around the two flat ends of cylinder (longitudinal separation, LS). At low Aspect Ratio On the middle cross-section, the flow pattern bears a great difference from the 2-dimensional flow (over a very long cylinder) that a singular source appears in the wake, together with TS to form a distorted star-shaped streamline pattern. The singular source is located in the farthest spot from the cylinder where recirculation of LS starts in the middle section; the normalized distance between the singular source and the cylinder is denoted by d_s. the strength of the singular source, denoted by SS=-∂v/∂y, The flow conditions of each cylinder are basically the same at Re = 10, and the wake area continues to elongate after increasing Re, while SS at Re = 100 will decrease significantly after Ar <3 When Ar is fixed, d_s grows by increasing the Reynolds number, and ss grows nonlinear after Re>40. | en |
dc.description.provenance | Made available in DSpace on 2021-06-16T09:26:45Z (GMT). No. of bitstreams: 1 U0001-1408202001004200.pdf: 7901120 bytes, checksum: fbe4dd741656c7c99a6c3afe6616d746 (MD5) Previous issue date: 2020 | en |
dc.description.tableofcontents | 致謝 i 中文摘要 ii Abstract iii 目錄 v 圖目錄 viii 表目錄 xiii 第1章 緒論 1 1.1 研究背景與動機 1 1.2 單圓柱 2 1.2.1 單圓柱相關文獻 2 1.3 有限圓柱相關文獻 4 1.3.1 有限圓柱流況相關文獻 4 1.3.2 有限圓柱模型相關文獻總結 9 1.4 阻力係數相關文獻 9 1.4.1 阻力係數文獻總結 13 1.5 史特豪數 13 1.6 Vortex shedding 抑制現象文獻回顧 14 第2章 基礎理論 16 2.1 參數介紹 16 2.1.1 圓柱參數介紹 16 2.2 基本公式推導 17 2.3 均勻流: 18 2.4 連續方程式 20 2.5 動量方程式 22 第3章 實驗方法 25 3.1 實驗設備 25 3.1.1 水平式循環水洞 25 3.1.2 可視化粒子 26 3.1.3 雷射光頁產生器 27 3.1.4 高速攝影機 28 3.1.5 Nikon鏡頭 29 3.1.6 相機 30 3.1.7 Load cell 31 3.1.8 音叉式黏度計 32 3.1.9 LDA系統 34 3.1 LDA法 34 3.2 PIV法 35 3.2.1 PIVLAB 36 3.2.2 實驗材料: 38 3.2.3 實驗架設 40 第4章 數值方法 43 4.1 網格建構 43 4.1.1 網格類型 43 4.1.2 網格設定 44 4.1.3 邊界條件 44 4.2 控制方程式 45 4.3 數值方法 45 4.3.1 分離求解器 46 4.3.2 空間離散 46 4.3.3 時間離散 49 4.3.4 壓力-速度耦合關係 50 第5章 實驗結果與討論 52 5.1 流場驗證 52 5.1.1 加上板流場驗證 52 5.1.2 無上板流場驗證 56 5.1.3 有限長度圓柱入口條件驗證 61 5.1.4 單圓柱流場可視化 63 5.1.5 單圓柱頻率 65 5.2 有限圓柱分析 66 5.2.1 有限圓柱流況 66 5.2.2 點源線源發生時機 82 5.2.3 有限圓柱源之強度 83 5.3 有限圓柱阻力係數 84 5.3.1 壁面邊界層對流場阻力係數的影響 84 5.3.2 CFD阻力係數計算 84 5.3.3 實驗阻力係數量測 86 5.4 Vortex shedding 抑制現象 92 5.4.1 實際量測到的Rec 92 第6章 結論與未來展望 94 6.1 結論 94 6.2 未來展望 95 參考文獻 96 | |
dc.language.iso | zh-TW | |
dc.title | 低雷諾數下流經有限長圓柱體之流場的端效應研究 | zh_TW |
dc.title | On the end effects of flow past a circular cylinder with finite span at low Reynolds numbers | en |
dc.type | Thesis | |
dc.date.schoolyear | 108-2 | |
dc.description.degree | 碩士 | |
dc.contributor.coadvisor | 張建成(Chien-Cheng Chang) | |
dc.contributor.oralexamcommittee | 張家歐(Chia-Ou Chang),郭光輝(GUANG-HUI GUO),謝政達(ZHENG-DA XIE) | |
dc.subject.keyword | 有限長度圓柱,渦旋脫離,低雷諾數,甘油, | zh_TW |
dc.subject.keyword | finite length cylinder,vortex shedding,low Reynold number,glycerin, | en |
dc.relation.page | 98 | |
dc.identifier.doi | 10.6342/NTU202003354 | |
dc.rights.note | 有償授權 | |
dc.date.accepted | 2020-08-18 | |
dc.contributor.author-college | 工學院 | zh_TW |
dc.contributor.author-dept | 應用力學研究所 | zh_TW |
顯示於系所單位: | 應用力學研究所 |
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