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| DC 欄位 | 值 | 語言 |
|---|---|---|
| dc.contributor.advisor | 宋家驥 | |
| dc.contributor.author | Yi-An Chiang | en |
| dc.contributor.author | 蔣宜安 | zh_TW |
| dc.date.accessioned | 2021-06-17T01:45:39Z | - |
| dc.date.available | 2022-08-20 | |
| dc.date.copyright | 2017-08-20 | |
| dc.date.issued | 2017 | |
| dc.date.submitted | 2017-07-26 | |
| dc.identifier.citation | [1] J. A. McFadden, 'Radial Vibrations of Thick‐Walled Hollow Cylinders,' The Journal of the Acoustical Society of America, vol. 26, no. 5, pp. 714-715, 1954.
[2] P. M. Naghdi and R. M. Cooper, 'Propagation of Elastic Waves in Cylindrical Shells, Including the Effects of Transverse Shear and Rotatory Inertia,' The Journal of the Acoustical Society of America, vol. 28, no. 1, pp. 56-63, 1956. [3] D. C. Gazis, 'Three‐Dimensional Investigation of the Propagation of Waves in Hollow Circular Cylinders. I. Analytical Foundation,' The Journal of the Acoustical Society of America, vol. 31, no. 5, pp. 568-573, 1959. [4] A. H. Fitch, 'Observation of Elastic‐Pulse Propagation in Axially Symmetric and Nonaxially Symmetric Longitudinal Modes of Hollow Cylinders,' The Journal of the Acoustical Society of America, vol. 35, no. 5, pp. 706-708, 1963. [5] A. E. Armenakas, D. C. Gazis, and G. Herrmann, Free vibrations of circular cylindrical shells. Pergamon Press, 1969. [6] W. Mohr and P. Holler, 'On Inspection of Thin-Walled Tubes for Transverse and Longitudinal Flaws by Guided Ultrasonic Waves,' IEEE Transactions on Sonics and Ultrasonics, vol. 23, no. 5, pp. 369-373, 1976. [7] J. J. Ditri and J. L. Rose, 'Excitation of guided elastic wave modes in hollow cylinders by applied surface tractions,' Journal of Applied Physics, vol. 72, no. 7, pp. 2589-2597, 1992. [8] P. Wilcox, M. Lowe, and P. Cawley, 'The effect of dispersion on long-range inspection using ultrasonic guided waves,' NDT & E International, vol. 34, no. 1, pp. 1-9, 2001. [9] T. R. Hay and J. L. Rose, 'Flexible PVDF comb transducers for excitation of axisymmetric guided waves in pipe,' Sensors and Actuators A: Physical, vol. 100, no. 1, pp. 18-23, 2002. [10] M. D. Beard and M. J. S. Lowe, 'Non-destructive testing of rock bolts using guided ultrasonic waves,' International Journal of Rock Mechanics and Mining Sciences, vol. 40, no. 4, pp. 527-536, 2003. [11] M. D. Beard, M. J. S. Lowe, and P. Cawley, 'Ultrasonic Guided Waves for Inspection of Grouted Tendons and Bolts,' Journal of Materials in Civil Engineering, vol. 15, no. 3, pp. 212-218, 2003. [12] F. Chati, F. Léon, M. El Moussaoui, A. Klauson, and G. Maze, 'Longitudinal mode L(0,4) used for the determination of the deposit width on the wall of a pipe,' NDT & E International, vol. 44, no. 2, pp. 188-194, 2011. [13] S.-H. Ni, Y.-Z. Yang, P.-H. Tsai, and W.-H. Chou, 'Evaluation of pile defects using complex continuous wavelet transform analysis,' NDT & E International, vol. 87, pp. 50-59, 2017. [14] 楊帆, '管道超聲導波檢測信號分析處理与識別研究,' 碩士論文, 西南石油大學, 2012. [15] 顧軍, '超聲導波在管中的頻散特性及實驗研究,' 碩士論文, 大連理工大學, 2009. [16] 田鳳彬, '管道超聲導波檢測系統构建及信號處理方法研究,' 碩士論文, 河北科技大學, 2012. [17] 胡广书, 现代信号处理教程. 清华大学出版社, 2004. [18] 王裕賢, '以連續小波轉換分析土層表面波波速之研究,' 碩士論文, 營建工程系, 朝陽科技大學, 2010. [19] Mathworks. Wavelet Toolbox Documentation. Available: https://www.mathworks.com/help/wavelet/ref/scal2frq.html?searchHighlight=scal2frq&s_tid=doc_srchtitle [20] 諸娟娟, '用於超聲導波檢測的激勵電源設計,' 碩士論文, 電子訊息與電氣工程學院, 上海交通大學, 2011. [21] A. Devices, 'Low Power, 12.65 mW, 2.3V to 5.5V, Programmable Waveform Generator.' [22] M. Technology, 'Single/Dual Digital Potentiometer with SPI™ Interface.' [23] 何. 杜肇申, 電子學實習I. 新文京出版社, 2015. [24] A. Devices, '500 MHz Four-Quadrant Multiplier.' [25] A. Devices, 'Low Cost Low Power Instrumentation Amplifier.' | |
| dc.identifier.uri | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/67714 | - |
| dc.description.abstract | 近年來由於全球面臨能源短缺及環境污染等問題，綠能產業已成為各地致力發展的新趨勢，而基於台灣西部海域極佳的海上風場，離岸風機的發展也漸漸地受到重視。但風機之基樁位處複雜的海洋環境中，容易受到潮汐或地震等外力作用而影響其包覆之穩定度。
因此本文研究將基樁簡化為單一鋼管模型，設計一套用於包覆程度檢測的導波量測系統，由於其量測依據為特定模態之回波衰減量，因此導波模態的激發與回波辨識是本文的重點。系統內包含自製之發射電路及壓電陶瓷陣列，回波訊號的辨識則使用時頻轉換，將其結果與PCdisp繪出之頻散曲線圖做對照，即從時間和頻率上比較實際量測訊號與理論值之相關性。分析結果則顯示出在不同環境下，此系統激發與加強之模態均與理論值相符合，能夠將其進一步的應用於振幅衰減的檢測上。 | zh_TW |
| dc.description.abstract | Due to the shortage of global energy and the Environmental pollution issues, the industry of green energy has become a new trend of development in recent years. Based on the great wind field in offshore western Taiwan, the development of offshore wind turbines were taken more seriously. But the foundation of the pile in the complex marine environment, affected by the external forces like tide or earthquake easily and make it unstable.
As a result, this paper uses a single steel pipe as the model and designs a guided-wave measurement system for the detection of the pile. The detection is based on the specific mode of the echo attenuation, so the excitation of the mode and the identification of the echo signal is the focus in this paper. This system includes self-made transmmitting circuit and piezoelectric ceramic array. The echo signal is identified by time-frequency conversion and compared with the dispersion curve plotted by PCdisp, which means to compare the correlation between the actual measurement signal and the theoretical value. The results of the analysis shows that the modes be excited and enhanced in this system are in agreement with the theoretical values in different environments, which means it can be applied to the detection of the amplitude attenuation. | en |
| dc.description.provenance | Made available in DSpace on 2021-06-17T01:45:39Z (GMT). No. of bitstreams: 1 ntu-106-R02525083-1.pdf: 2505697 bytes, checksum: bf8bc81a96207262244e58ad10ce81c7 (MD5) Previous issue date: 2017 | en |
| dc.description.tableofcontents | 目錄
誌謝 I 中文摘要 II ABSTRACT III 第 1 章 緒論 1 1.1 研究動機與目的 1 1.2 文獻回顧 2 1.3 論文架構 3 第 2 章 背景理論 4 2.1 導波於圓管中傳遞之波動方程式 4 2.1.1 縱向模態 7 2.1.2 扭矩模態 8 2.1.3 撓曲模態 9 2.2 頻散曲線 9 2.2.1 相速度與群速度 10 2.2.2 導波模態選擇 10 2.3 時頻分析 13 2.3.1 短時傅立葉轉換(STFT) 13 2.3.2 連續小波轉換(CWT) 16 第 3 章 實驗架構及量測方法 18 3.1 訊號產生電路設計 18 3.1.1 DDS模組(Direct Digital Synthesizer Module) 19 3.1.2 箝位電路(Clamping Circuit) 20 3.1.3 振幅調變 21 3.1.4 整體電路圖及輸出波形 23 3.2 實驗架構 25 3.3 實驗量測方法 28 第 4 章 實驗結果與討論 30 4.1 STFT與小波轉換結果之比較 33 4.1.1 不同時間長度窗函數下的STFT結果 33 4.1.2 不同尺度序列長度下之小波轉換結果 35 4.2 時頻轉換與頻散曲線之對照 36 4.3 結果討論 38 第 5 章 結論與未來展望 39 5.1 結論 39 5.2 未來展望 40 參考文獻 41 | |
| dc.language.iso | zh-TW | |
| dc.subject | 離岸風機基樁 | zh_TW |
| dc.subject | 頻散曲線圖 | zh_TW |
| dc.subject | PCdisp | zh_TW |
| dc.subject | 導波法 | zh_TW |
| dc.subject | Guided wave method | en |
| dc.subject | Offshore wind turbine | en |
| dc.subject | Foundation piles | en |
| dc.subject | dispersion curve | en |
| dc.subject | PCdisp | en |
| dc.title | 導波檢測系統之開發與驗證 | zh_TW |
| dc.title | Development and Verification of the Guided Wave Detection System | en |
| dc.type | Thesis | |
| dc.date.schoolyear | 105-2 | |
| dc.description.degree | 碩士 | |
| dc.contributor.oralexamcommittee | 黃心豪,王昭男,黃翊鈞 | |
| dc.subject.keyword | 導波法,離岸風機基樁,頻散曲線圖,PCdisp, | zh_TW |
| dc.subject.keyword | Guided wave method,Offshore wind turbine,Foundation piles,dispersion curve,PCdisp, | en |
| dc.relation.page | 42 | |
| dc.identifier.doi | 10.6342/NTU201702057 | |
| dc.rights.note | 有償授權 | |
| dc.date.accepted | 2017-07-27 | |
| dc.contributor.author-college | 工學院 | zh_TW |
| dc.contributor.author-dept | 工程科學及海洋工程學研究所 | zh_TW |
| 顯示於系所單位： | 工程科學及海洋工程學系 | |
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| ntu-106-1.pdf 未授權公開取用 | 2.45 MB | Adobe PDF |
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