本研究將探討一二維方柱體在受強制振動影響下，改變其橫風向與扭轉向振動間的頻率比及二維方柱之偏心量，進而瞭解橫風向與扭轉向振動間發生耦合時，結構物所產生之氣動力現象。
結果顯示，當Fr大於1.0時，在勁度中心往上游偏離，偏心量為10％時可得最小的擾動昇力係數峰值及渦散頻率的尾跡風速；而在勁度中心往上游偏離，偏心量為20％可得最大的擾動昇力係數峰值及渦散頻率的尾跡風速。當Fr等於1.0時，在勁度中心往上游偏離，偏心量為10％時可得最大的擾動昇力係數峰值及渦散頻率的尾跡風速；而在勁度中心往上游偏離，偏心量為20％可得最小的擾動昇力係數峰值及渦散頻率的尾跡風速。與Fr大於1.0正好相反。當Fr小於1.0時，在勁度中心無偏離時，可得最大的擾動昇力係數峰值及渦散頻率的尾跡風速；而最小值則不一定發生在哪一個偏心上。

Wind tunnel measurements were performed to study the aerodynamic 
phenomenon of a two dimensional prism when the mass center separates from the center in transverse and torsional coupled vibration modes.
  
  When the torsion/transverse frequency ratio (Fr) is greater than 1.0, as long as the eccentricity is introduced in the upstream direction at 10%, the spectral peaks of the lift fluctuation coefficient and the vortex shedding reach a minimum value compared with other eccentricities. However, as the eccentricity increases to 20%, the spectral peaks reach a maximum value.

Whereas when Fr=1, eccentricity 10% and 20% in the upstream direction, the spectral peaks of lift fluctuation coefficient and vortex shedding show the opposite trend. A maximum value is obtained when Fr is smaller than 1.0 and without eccentricity. However, there is no obvious trend for the minimum value.

摘要
目錄	Ⅰ
圖目錄	Ⅳ


第一章　緒論
1-1	前言……………………………………………………...…1
1-2	研究動機………………………………………………..….1
1-3	研究方法與內容……………………………………………2

第二章　文獻回顧
2-1	結構物振動…………………………………………….…….4
2-2	橫風向振動…………………………………………………..5
2-2-1	橫風向振動對壓力係數的影響……………………..…...6
2-2-2	橫風向振動對尾跡反應的影響……………….………....9
2-3　扭轉向振動.…………………………………….……….…..10
2-4	壓力之量測..…………………………………………....…..14
2-5	尾跡之量測…………………………………………..…..…14
第三章　理論背景介紹
3-1	風對結構物之作用……………………………………....…..16
3-1-1分離 (separation)…………………………………………..16
3-1-2再接觸現象(reattachment)…………………………………16
3-1-3 尾跡(wake)………………………………………………..17
3-1-4 渦散作用(vortex shedding)……………………………….17
3-1-5 鎖定現象(lock-in)…………………………………………18
3-2	端板效應(end plate effect)…………………….….………….19
3-3	阻塞比效應(blockage ratio effect)………………………..….20
3-4	雷諾數效應(Reynolds number effect)…...……………….….20
3-5	均勻紊流場(homogeneous turbulence flow)………....…..….21
  3-5-1 紊流強度(turbulence intensity)……………………………21
3-6	風力係數(wind coefficient)…………………………………..23
3-7	數位訊號之處理與分析技巧………………………………..25
3-8	散漫數據分析(random data analysis)………………………..26
第四章　結果與討論
4-1	風洞簡介…………………………………………………….29
4-2	結構之模擬…………………………………….……………29
4-2-1	結構物外型設計………………………………................29
4-2-2	結構物偏心…………………………..…………………..29
4-3	實驗設置……………………………....................................30
4-3-1	實驗參數……...................................................................30
4-3-2	實驗種類包括……….…………………………………..31
4-4	實驗設備……………………………………………………32
4-4-1	強制振動扭轉基台…..………………………………….32
4-4-2	流場風速量測設置……………………………………..32
4-4-3	模型壓力量測設置……………………………………..33
4-4-4	尾跡風速的量測………………………………………...34
4-5	率定與校正…..……………………………………………..34
4-5-1	TSI定溫式熱膜探針之率定……………..…….………34
4-5-2	壓力轉換器之率定.…………………..…………………35
4-5-3	管線系統訊號之校正……….....………………………..35
4-6	位移反應量測與率定………................................................37
  4-6-1結構位移之量測………………………………………….37
  4-6-2位移率定………………………………………………….38
第五章　結果與討論
5-1   實驗種類…………………………………..…….…………39
5-2   實驗參數………………………………………………..….39
5-3   擾動昇力係數的實驗結果…………………………………40
5-4   尾跡反應的實驗結果……………………………………….46
5-5   討論………………………………………………………….51
第六章　結論

參考文獻……………………………………………………………......54








 
圖  目  錄
圖4-1淡江大學風洞實驗室配置圖……………………………………61
圖4-2昇力模型壓力孔位置示意圖.....………………………………..62
圖4-3模型偏心示意圖…………………….…………………………..63
圖4-4二軸平台之馬達…………………………………………………64
圖4-5振動平台架設圖………………….……………………………..64
圖4-6皮拖管………….………………………………………………..65
圖4-7昇力量測流程圖…………………………………………………66
圖4-8探針之架設………………………………………………………67
圖4-9 IFA-100智慧型流速儀…………………………………………67
圖4-10管線系統校正流程圖…………………………………………..68
圖4-11實驗採樣分析流程圖…………………………………………..69
圖4-12 Labview儀控程式……………………………………………..70
圖4-13 Labview取值程式……………………………………………70
圖5-1方柱模型在耦合實驗中當F=1.2時，各順風向偏心量之擾動昇力係數尖峰值…………………………………………………71
圖5-2方柱模型在耦合實驗中當F=1.1時，各順風向偏心量之擾動昇力係數尖峰值………………………………………………….71
圖5-3方柱模型在耦合實驗中當F=1.0時，各順風向偏心量之擾動昇
力係數尖峰值……….……………………………………….72
圖5-4方柱模型在耦合實驗中當F=0.9時，各順風向偏心量之擾動昇力係數尖峰值………………………………………………..72
圖5-5方柱模型在耦合實驗中當F=0.8時，各順風向偏心量之擾動昇力係數尖峰值…………………………………………………73
圖5-6方柱模型在耦合實驗中當Ex=20%時，各順風向偏心量之擾動昇力係數尖峰值…………………………………………………74
圖5-7方柱模型在耦合實驗中當Ex=10%時，各順風向偏心量之擾動昇力係數尖峰值…………………………………………………74
圖5-8方柱模型在耦合實驗中當Ex=20%時，各順風向偏心量之擾動昇力係數尖峰值…………………………………………………75
圖5-9方柱模型在耦合實驗中當Ex=-10%時，各順風向偏心量之擾動昇力係數尖峰值………………………………………………75
圖5-10方柱模型在耦合實驗中當Ex=-20%時，各順風向偏心量之擾動昇力係數尖峰值……………………………………………..76
圖5-11方柱模型在各順風向偏心量，不同頻率比共振點之擾動昇力係數尖峰值…………………………………………………..77
圖5-12方柱模型在耦合實驗中當F=1.2時，各順風向偏心量之尾跡風速尖峰值………………………………………………….78
圖5-13方柱模型在耦合實驗中當F=1.1時，各順風向偏心量之尾跡風速尖峰值……………………………………………………78
圖5-14方柱模型在耦合實驗中當F=1.0時，各順風向偏心量之尾跡風速尖峰值……………………………………………………….79
圖5-15方柱模型在耦合實驗中當F=0.9時，各順風向偏心量之尾跡風速尖峰值………………………………………………………79
圖5-16方柱模型在耦合實驗中當F=0.8時，各順風向偏心量之尾跡風速尖峰值………………………………………………………80
圖5-17方柱模型在耦合實驗中當Ex=20%時，各順風向偏心量之尾跡風速尖峰值……………………………………………………81
圖5-18方柱模型在耦合實驗中當Ex=10%時，各順風向偏心量之尾跡風速尖峰值……………………………………………………81
圖5-19方柱模型在耦合實驗中當Ex=0%時，各順風向偏心量之尾跡風速尖峰值………………………………………………………82
圖5-20方柱模型在耦合實驗中當Ex=-10%時，各順風向偏心量之尾跡風速尖峰值……………………………………………………82
圖5-21方柱模型在耦合實驗中當Ex=-20%時，各順風向偏心量之尾跡風速尖峰值……………………………………………………83

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