近年來質點影像測速儀已經廣泛地運用在量測各種流場，其優點是可以在不干擾流場的情況下對流場作全域性的觀測，而方法是首先在流場中產生一光頁再加入適當的質點並且用CCD攝影機將流場影像紀錄下來，然後加以數位化再透過統計學上的相關性分析而間接得到流場的位移。另外在實驗的同時並且可以將流場加以可視化而作進一步定性與定量上的分析，因此本實驗將利用此方式之特性探討流體通過圓柱後之尾流流場。在實驗中將針對於低雷諾數下對尾流流場加以動量干擾，並且改變不同的參數，包括有動量干擾的形式、動量的干擾大小以及干擾之角度，分析在受到這些效應後是否可以抑制尾流的產生，同時避免流場中存在著固定的頻率而導致流體引致震動的發生。由實驗結果可以發現，當於圓柱後方0˚角時注入動量可以破壞掉尾流結構使尾流影響區域縮小，並且避免固定頻率之渦漩剝離之發生。而於30˚及60˚時於圓柱後方吸出動量，則可以破壞剪力層避免速度梯度的的產生，而使得流場變的均勻。同時於上述的結果中顯示，動量干擾量的增加也有助於降低尾流影響的區域及消弭尾流的產生。

Particle image velocimetry was widely used in many kinds of flow field recently. It provides a global view of instantaneous fluid velocity without disturbs flow field. In the present study, the cylinder wake with momentum addition was measured by PIV. The Reynolds number was fixed at 465 and 535 with cylinder diameter 19mm. The flow’s displacement was measured by tracking flow images of 50 diameter ployamid 12 particles. The mean velocity of the momentum interference from the cylinder surface were 21 and 52 mm/s, respectively. From the results, the wake region shrinks under momentum injection at 0˚, but enlarges at 30˚ to 90˚. Under momentum suction, the effect of the wake expands at 0˚. Although the down stream velocity becomes more uniform at 30˚ and 60˚, the wake region spreads when suction at 90˚. On the other hand, the velocity spectra by hot-film anemometry also give consistent results with PIV analysis.

論文摘要(中文) ---------------------------------------------------- Ⅰ
論文摘要(英文) ---------------------------------------------------- Ⅱ
目錄 ------------------------------------------------------------------- Ⅲ
表目錄 ---------------------------------------------------------------- Ⅴ
圖目錄 ---------------------------------------------------------------- Ⅵ
符號說明 ------------------------------------------------------------- XIII

第一章 緒論 -------------------------------------------------------- 1
1-1 前言 --------------------------------------------------------- 1
1-2 文獻回顧 ---------------------------------------------------- 2
1-3 研究方法 ---------------------------------------------------- 6
1-4 預期目標 ---------------------------------------------------- 7
第二章 實驗儀器設備與方法 ----------------------------------- 8
2-1 實驗設備 ---------------------------------------------------- 8
2-2 PIV的理論分析 --------------------------------------------- 11
2-3 實驗步驟 ---------------------------------------------------- 12
2-4 數據分析 ---------------------------------------------------- 13
2-5 誤差 --------------------------------------------------------- 14
第三章 結果與討論 ----------------------------------------------- 16
3-1 均勻流場之測試 -------------------------------------------- 16
3-2 無動量干擾之圓柱尾流場分析 ---------------------------- 16
3-3 穩定注入動量之圓柱尾流場分析 ------------------------- 17
3-4 穩定吸出動量之圓柱尾流場分析 ------------------------- 20
3-5 流場之動量損失 ------------------------------------ 24
3-6 流場之頻譜分析 ------------------------------------ 24
第四章 結論與建議 ---------------------------------------------- 26
4-1 結論 -------------------------------------------------------- 26
4-2 建議 -------------------------------------------------------- 28
參考文獻 ----------------------------------------------------------- 29
附錄 ----------------------------------------------------------------- 111

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