淡江大學機構典藏:Item 987654321/36024
English  |  正體中文  |  简体中文  |  Items with full text/Total items : 62079/94651 (66%)
Visitors : 1639810      Online Users : 14
RC Version 7.0 © Powered By DSPACE, MIT. Enhanced by NTU Library & TKU Library IR team.
Scope Tips:
  • please add "double quotation mark" for query phrases to get precise results
  • please goto advance search for comprehansive author search
  • Adv. Search
    HomeLoginUploadHelpAboutAdminister Goto mobile version
    Please use this identifier to cite or link to this item: https://tkuir.lib.tku.edu.tw/dspace/handle/987654321/36024


    Title: 二維方柱橫向與扭轉向振動耦合之氣動力研究
    Other Titles: Aerodynamic forces of a square prism in transverse and torsional coupled motion
    Authors: 呂宜靜;Lu, Yi-ching
    Contributors: 淡江大學水資源及環境工程學系碩士班
    盧博堅;Lu, Po-chien
    Keywords: 二維方柱;強制振動;頻率比;偏心量;A square prism;forced vibration;ratio of frequency;eccentricity
    Date: 2005
    Issue Date: 2010-01-11 07:29:12 (UTC+8)
    Abstract: 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.
    Appears in Collections:[Graduate Institute & Department of Water Resources and Environmental Engineering] Thesis

    Files in This Item:

    File SizeFormat
    0KbUnknown342View/Open

    All items in 機構典藏 are protected by copyright, with all rights reserved.


    DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU Library & TKU Library IR teams. Copyright ©   - Feedback