本實驗應用應變規建立水洞中單一圓柱的受力量測系統，探討單一圓柱在橫流中，有無動量注入的受力情形，動量經由圓柱表面狹縫注入以干擾圓柱之尾流。應變規貼於一扁平的不鏽鋼板上，在本實驗範圍內，輸出電壓與受力大小可獲得一良好的正比關係，應用此系統量測不同的注入量及角度干擾下，圓柱的升力、阻力的大小。實驗結果顯示，動量注入對圓柱的影響甚鉅，動量注入於圓柱正後方流場，可以有效地降低圓柱所受阻力，隨著雷諾數的提高，應增加動量干擾的量，以維持動量干擾的有效性，動量注入有垂直於自由流方向的分量時，升力則有明顯的改變。

This research shows an experimental set-up of measuring forces acting on single cylinder in cross flow provided by a water tunnel. Water was also released at various directions from the cylinder surface to study the effect of momentum injection on cylinder forces. The fluid forces on the cylinder was measured by a strain gauge bonded on long-thin plat which is connected to the cylinder. The drag and lift coefficients of the cylinder were measured with momentum injection of various direction and magnitude. Experimental results show that the drag coefficient is effectively reduced with momentum injection at streamwise direction. Negative drag coefficient (propulsion) can be obtained if the magnitude of momentum inject is large enough. When the momentum injection has cross-stream component, lift force is obtained with its value depending on the magnitude of momentum injection. For higher Reynolds number, the magnitude of momentum injection has to be increased to maintain the effectiveness of momentum injection.

目錄

論文摘要(中文) ------------------------------------ I
論文摘要(英文) -------------------------------------II
目錄 -----------------------------------------------III
圖目錄 ---------------------------------------------IV

第一章 序論 ------------------------------------------1
1.1 前言 ------------------------------------------- 1
1.2 文獻回顧 ----------------------------------------2
1.3 研究方法 ----------------------------------------4
第二章 實驗儀器設備與方法 ----------------------------6
2.1 實驗設備 ----------------------------------------6
2.2 實驗步驟 --------------------------------------- 9
2.3 數據分析 --------------------------------------- 11
2.4 誤差 ------------------------------------------- 12
第三章 結果與討論 ----------------------------------- 15
3.1 零度角動量干擾 --------------------------------- 15
3.2 45度角動量干擾 --------------------------------- 17
3.3 60度角動量干擾 --------------------------------- 18
3.4 90度角動量干擾 --------------------------------- 19
3.5 不同角度的動量干擾比較 ------------------------- 21
第四章 結論與建議 ----------------------------------- 23
4-1 結論 ------------------------------------------- 23
4-2 建議與改進-------------------------------------- 24
參考文獻 -------------------------------------------- 27
附錄 ------------------------------------------------ 54

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