本研究的對象為一圓柱尾流，外加流體動量以干擾此一尾流場，加入流體的方式首先採用穩態的注射（Steady injection）方式干擾，去影響邊層（Boundary layer）。再者，採用來回振盪的吸噴流（Oscillatory jet），以不同的頻率和振幅，注入圓柱體尾端。以實驗為主探討流體注入對尾流的效應，包括此渦漩結構的大小、強度或頻率呈何種變化，此吸噴頻率與流場的特徵頻率有無關係，吸噴的質量或動量大小對流場呈現何種影響。實驗結果發現穩定動量注入圓管尾流可大幅縮減圓管後wake region內紊流強度大小，在Re=300~1200間動量注入Uj/Uup=8~10之間能將使得紊流強度下降80%以上，尾流區亦縮小45%以上，穩定動量注入以降低紊流強度隨著Re增加愈顯困難;往覆動量注入方面則改變注入頻率與每次動量注入大小亦發現相對應變化。Re=300~1200間，固定動量注入大小逐步調整注入頻率從0至0.6其圓管後方紊流強度隨頻率增加相對逐漸減小，在注入頻率為0.3hz至0.45hz則有相反趨勢，頻率增加相對紊流強度增加，但當注入頻率大於0.45hz則又恢復頻率增加紊流強度降低趨勢。於Re=300~1200，當固定動量注入頻率為0.4hz，逐步增加每次注入或吸入動量大小，亦發現固定頻率下動量注入愈大紊流強度會相對減小，但是亦有一有效範圍並非線性遞減;Re=300，有效範圍0 ≦ Umax/Uup ≦ 15.8，當大於15.8則紊流強度相對增加; Re = 530有效範圍0 ≦ Umax/Uup ≦ 10.3，當大於10.3則紊流強度相對增加; Re=660有效範圍0 ≦ Umax/Uup ≦ 8，當大於8則紊流強度相對增加。

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目錄

摘 要……………………………………………………………………i
目錄……………………………………………………………………..ii
圖目錄…………………………………………………………………..iv
符號說明………………………………………………………………..x
第一章緒論……………………………………………………………..1
1-1. 研究緣由與動機……………………………………………….1
1-2. 文獻回顧………………………………………………………..1
1-3. 研究重點………………………………………………………...2
第二章、實驗設備與方法……………………………………………….4
2-1 實驗設備…………………………………………………………4
2-2. 實驗方法………………………………………………………...8
三、實驗結果與討論……………………………………………………10
3-1. 未注入動量之圓柱尾流流場分析…………………………….10
3-2. 穩定動量注入圓柱後尾流之流場分析……………………….12
3-3. 往覆動量注入圓柱後尾流之流場分析……………………….15
第四章 結論與建議……………………………………………………20
參考文獻………………………………………………………………..22
附錄A………………………………………………………………….87
附錄B…………………………………………………………………..89
附錄C…………………………………………………………………..90
附錄D…………………………………………………………………..91
附錄E…………………………………………………………………...92
附錄F…………………………………………………………………...93

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