Detection of a crack and its location and development of diagnosis system by modal analysis and wavelet

模态分析和小波的裂纹检测、定位及诊断系统开发

• 批准号: 14550215
• 负责人: ISHIDA Yukio
• 金额: $ 2.62万
• 依托单位: Nagoya University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2002
• 资助国家: 日本
• 起止时间: 2002 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-14550215/
• 关键词: Rotating machinery; Vibration diagnosis; Crack; Resonance; Nonlinear oscillation; 回転軸; クラック; 疲労; 共振現象

The early detection of a crack is very important because it causes a serious accident. In this research, we investigated the means to find the occurrence and the location of a crack. The contents are classified into two subjects.First, the changes of resonance curves or responses of steady-state oscillations and nonstationary oscillations due to the magnitude and the direction of the unbalance are investigated theoretically and experimentally. As a result, it is clarified that a remarkable change, such as, the occurrence of unstable range, occurs in a steady-state oscillation of a cracked shaft. It is also found that the response curve of a nonstationary oscillation of a cracked shaft changes depending on the location of a crack.Secondly, the means to find a crack by sweeping the frequency of the external excitation besides unbalance force is investigated. By experiments, it is clarified that new resonances occur due to a crack. By FEM analysis, it is clarified that the kinds and magnitudes of resonance, the kinds of predominant frequency spectrums changes due to the location of a crack. This result suggests that it is possible to specify the occurrence and the location of a crack if these data are analyzed totally.

裂缝的早期检测非常重要，因为它会导致严重的事故。在这项研究中，我们调查的手段来找到裂纹的发生和位置。主要内容分为两个方面：首先，从理论和实验上研究了不平衡量的大小和方向对稳态振动和非稳态振动的共振曲线或响应的影响。其结果是，它是明确的，一个显着的变化，如出现不稳定的范围，发生在一个裂纹轴的稳态振荡。研究还发现，裂纹轴的非平稳振动响应曲线随裂纹位置的变化而变化。其次，研究了除不平衡力外，通过扫描外激励频率来发现裂纹的方法。通过实验，阐明了由于裂纹而发生的新的共振。通过有限元分析，阐明了共振的种类和幅值以及主频谱的种类因裂纹位置的不同而发生变化。这一结果表明，如果对这些数据进行全面分析，就有可能确定裂纹的发生和位置。

项目成果

石田幸男, 井上剛志: "周期的加振によるロータクラックの検出"日本機械学会論文集C編. 70. 1-8 (2004)

Yukio Ishida、Tsuyoshi Inoue：“通过周期性励磁检测转子裂纹”，日本机械工程师学会会议录，C 版（2004 年）。

Y.Ishida, T.Inoue, H.Kondo: "Nonstationary Oscillations of a Cracked Rotor"Proceedings of International Symposium on Machine Condition Monitoring and Diagnosis. 144-150 (2002)

Y.Ishida、T.Inoue、H.Kondo：“裂纹转子的非平稳振荡”机器状态监测与诊断国际研讨会论文集。

Yukio Ishida, Tsuyoshi Inoue: "Detection of a crack by external excitations"Transactions of the JSMZE (in Japanese). Vol.70,No.4. 1-8 (2004)

Yukio Ishida、Tsuyoshi Inoue：“通过外部激励检测裂纹”JSMZE 交易（日语）。

Yukio Ishida, Tsuyoshi Inoue, Hideo Kondo: "Nonstationary Oscillations of a Cracked Rotor"Proceedings of International Symposium on Machine Condition Monitoring and Diagnosis. 144-150 (2002)

Yukio Ishida、Tsuyoshi Inoue、Hideo Kondo：“裂纹转子的非平稳振荡”机器状态监测与诊断国际研讨会论文集。

石田幸男, 井上剛志: "周期的加振によるロータクラックの検出"日本機械学会論文集C編. 70・692(発表予定). (2004)

Yukio Ishida、Tsuyoshi Inoue：“通过周期性励磁检测转子裂纹”，日本机械工程师学会会议录，C 版（2004 年）。