Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/2728
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dc.contributor.advisor鄔詩賢zh_TW
dc.contributor.advisorJ.S.S.Wuen_US
dc.contributor.author羅佐良zh_TW
dc.contributor.authorT.L.LOen_US
dc.date1999zh_TW
dc.date.accessioned2014-06-05T11:43:51Z-
dc.date.available2014-06-05T11:43:51Z-
dc.identifier.urihttp://hdl.handle.net/11455/2728-
dc.description.abstract在一般的動態問題中,不連續結構體間的接觸常常會引發剛性的改變,像是相互碰觸在一起的結構,或是鬆配合的結合件,甚至是偏心的軸承或鬆脫的螺絲等。這類不連續的結構體可能出現不可預知的自然振幅限制,因而產生無法預期的運動發生,當這些不可預知的振幅限制或是運動發生時,所產生結構自然振動型態的改變,對於高精密度的工程問題如飛行器的設計、高效率引擎,或是衛星結構系統的設計等,是有必要詳加討論研究的。 由於存在著一些不可預知的振幅限制發生的原因,所以在本研究中,針對比較重要的自由度給予振幅限制之條件,對於因此引發之受制運動,其運動方程式,可利用有關的數值分析方法加以研究討論,其中包含板殼的結構。本研究中不僅是探討結構體存在著自然振幅限制條件下的自然振動型態改變,而且提供一些在機械之安全設計上的重要參考依據。 本研究之結果說明自然振幅限制的位置及受制量的大小,會嚴重的影響整個系統的自然振動型態,而且受制的自然振幅位置越靠近結構體邊界時,系統會有更顯著的自然振動型態改變。在較大型結構物中限制自然振幅的位置,對於自然振動型態的改變量是比較小。此外振幅限制對於低頻的模態的影響更為顯著。zh_TW
dc.description.abstractContact of non-continuous structures may cause changes of it's rigidity and is a general problem occurred in most of the kinetics problems, such as copular structures, loose-match components, even wear down biased bearing or unfasten bolts, etc. Such kinds of non-continuous structures may obviously appear unpredictable constraints on the natural amplitudes causing unexpected motions. When unpredictable constraints or motions appear, the natural frequencies of such structures are changed and its natu-ral behaviors must be reconsidered. Such problems must be particularly considered for the design of high precision engineering systems such as aircraft design, advanced engine development, satellite system design, etc. In the study, general equations of motion for natural behaviors under constraints of motion (constraints on the vibrational amplitudes) caused by unpredictable reasons on some selected, significant degrees-of-freedom, are developed and some related fundamental numerical studies are per-formed, including plates and shells. This study may not only explore the effect of the amplitude constraints on natural behaviors of structures but also provide significant information for the safety machine design. The calculating results tell that the location and restricted magnitude on natural amplitudes may affect overall system natural behaviors seriously. When the boundary to restrict the natural amplitudes is more close to the structures, the more on the effect of the natural behaviors of the structures may appear. When the structures are large, the constraints of natural mo-tion will probably affect the natural frequencies considerable small de-pending on the location of the restriction. Furthermore, the low frequency modes may be affected by the restriction of amplitudes significantly.en_US
dc.description.tableofcontents誌 謝………………..…….……………………………………….I 中文摘要……………….……….……………………………….…...II 英文摘要……………… ……….……………………………….…..III 目 錄……………………….……………………………………IV 圖 目 錄….…..……….……..…………………..………………VII 表 目 錄……………………………….…………………………..XI 符號說明………………………………………………..…….….XII 第一章 緒論……………………….………………………………..1 1.1前言……………………….………………………………..1 1.2文獻回顧…………………………………………………...2 1.3研究方法與目的 ……………………………………….…3 第二章 自由振動之有限元素法…………………………………..5 2.1前言………..…………………………..……………………5 2.1.1分散式質量矩陣之計算…………………….…….….6 2.1.2勁度矩陣之計算…………………..………………….7 2.2特徵值問題………..….………………………….…….….. 8 第三章 振幅限制式自然振動頻率……..………………………..11 3.1 單一自由度彈簧系統剛性振幅限制式自然振動頻率…..11 3.1.1單一自由度彈簧系統剛性振幅限制式自然振動 頻率公式推導...…………………………….……...11 3.1.2單一自由度彈簧系統剛性振幅限制式自然振動 頻率公式討論....………………… ………………..14 3.1.3 單一自由度彈簧系統非剛性性振幅限制式自然 振動頻率公式推導………….………………………15 3.2三維剛性振幅限制式自然振動頻率……………………..17 3.2.1三維剛性振幅限制式自然振動頻率公式推導……..17 3.2.2三維剛性振幅限制式自然振動頻率公式討論……..20 3.2.3矩陣開方處理…….………...………………………..21 第四章 有限元素特性矩陣.………..……..………………………24 4.1衍架元素…………….……..……….……………………..24 4.2樑元素……………….…………..…..………….…………26 4.3三維平版元素……………………………………….…….28 第五章 實例與討論………………………………………………31 5.1剛性振幅限制式自然振動頻率計算過程之流程……..…31 5.2剛性振幅限制式自然振動頻率之計算規則…………..…32 5.3單一自由度彈簧系統………….………………………….33 5.4二自由度彈簧系統…………….….…………..…………..34 5.5一維錐型衍架結構……………….…..………….…….….38 5.6一維樑結構………..…………..……………….……….…41 5.7二維衍架結構……………….……………………….……45 5.8平面樑結構………………………………….……….……49 5.9空間衍架結構………………………………………..……53 5.10空間樑結構………………………..……….….…..….…..58 5.11三維板元素之盒狀樑……………..………………..….…63 5.12三維板元素之葉片結構…………………….………..…..69 第六章 結論與展望…………………….………………………...74 6.1結論…….…..……..……….……….……………..………..74 6.2展望.……………….…..………….……………….………75 附 錄 一:高斯積分法.……………………………………………76 附 錄 二:三角形空間板元素特性矩陣之推導……….………....79 參考文獻………………………………………………..…………...92 作者簡介…………………………………………………………….96zh_TW
dc.language.isoen_USzh_TW
dc.publisher機械工程學系zh_TW
dc.subjectcontact vibrationen_US
dc.subject接觸振動zh_TW
dc.subjectamplitudes constrainten_US
dc.subjectnatural frequencyen_US
dc.subject振幅限制zh_TW
dc.subject自然振動頻率zh_TW
dc.title變形受制機構自然振動行為之有限元素方法研究zh_TW
dc.titleStudies of the Finite Element Method on Natural Vibrational Behaviors of the Mechanism with Deflection Constraintsen_US
dc.typeThesis and Dissertationzh_TW
item.languageiso639-1en_US-
item.openairetypeThesis and Dissertation-
item.cerifentitytypePublications-
item.grantfulltextnone-
item.fulltextno fulltext-
item.openairecristypehttp://purl.org/coar/resource_type/c_18cf-
Appears in Collections:機械工程學系所
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