مدل‌سازی و تخمین کشیدگی طیفی در سیگنال‌های تابع پاسخ فرکانسی تیر آلومینیومی با بهره‌گیری از آنالیز مودال تجربی و پردازش سیگنال تطبیقی

نوع مقاله : مقاله علمی

نویسندگان
1 دانشجوی دکتری تخصصی مهندسی هوافضا، دانشکده تحصیلات تکمیلی، دانشگاه علوم و فنون هوایی شهید ستاری، تهران، ایران
2 دانشجوی دکتری تخصصی مهندسی مکانیک، دانشکده مهندسی مکانیک، دانشگاه علم و صنعت ایران، تهران، ایران
3 دانشجوی کارشناسی ارشد مهندسی هوافضا، دانشکده مهندسی مکانیک، دانشگاه علم و صنعت ایران، تهران، ایران
چکیده
حساسیت بالای تخمین کشیدگی طیفی، آن را به ابزار قدرتمندی برای تشخیص زودهنگام خرابی‌ها و ناپایداری‌های غیرخطی دینامیکی تبدیل کرده است. در این مطالعه، ابتدا به آنالیز مودال یک تیر آلومینیومی آزاد-آزاد در قالب سه رویکرد آزمایشگاهی، تحلیلی و عددی پرداخته شد. در بخش مودالی، پاسخ‌های دینامیکی تیر در شش نقطه با آزمایش ضربه چکش کالیبره شده ثبت شد. نتایج آزمایشگاهی با تحلیل سیگنال و بهره‌گیری از الگوریتم‌های پیشرفته، پارامترهای مودال شامل فرکانس‌های طبیعی، بردارهای مودال و پاسخ‌های فرکانسی با دقت بالای بیش از ۹۰% در مقایسه با نتایج تحلیلی و عددی کنار هم قرار گرفتند. مدل‌سازی عددی در آباکوس نشان داد که نتایج در فرکانس‌های ۸۰ تا ۱۸۰۰ هرتز با دقت قابل قبولی مطابقت دارد و توانسته است رفتار ارتعاشی سیستم را با خطای کم، شبیه‌سازی کند. در بخش دوم، تحلیل نشانه‌های دینامیکی و کشیدگی طیفی سیگنال تابع پاسخ فرکانسی، با روش‌های تبدیل موجک و تبدیل فوریه زمان-کوتاه انجام شد. نتایج این تحلیل نشان داد که در فرکانس ۲۵۵ هرتز، ناهنجاری دینامیکی قابل‌توجهی در مود ۲ با کیفیت فاکتور بالا (بیش از ۲۵) و کشیدگی در محدوده 5/4 تا 5/6 که نشان‌دهنده احتمال وجود ترک، شل‌شدگی یا تغییرات سختی در سازه است وجود دارد. این ناهنجاری در طول زمان پایداری داشته و با برهم‌کنش مودها و پدیده‌های غیرخطی همراه است.
کلیدواژه‌ها
موضوعات

عنوان مقاله English

Modeling and Estimation of Spectral Stretching in Aluminum Beam Frequency Response Function Signals Using Experimental Modal Analysis and Adaptive Signal Processing

نویسندگان English

محمد خاکباز 1
Alireza Ebrahimi Hesari 2
Amin Darani goldarreh 3
Mehrdad Karimi 1
1 PhD student in Aerospace Engineering, Faculty of Graduate Studies, Shahid Sattari Aeronautical University of Sciences and Technology, Tehran, Iran
2 PhD student in Mechanical Engineering, Faculty of Mechanical Engineering, Iran University of Science and Technology, Tehran, Iran
3 MSc student in Aerospace Engineering, Faculty of Mechanical Engineering, Iran University of Science and Technology, Tehran, Iran
چکیده English

The high sensitivity of spectral strain estimation has made it a powerful tool for early detection of failures and dynamic nonlinear instabilities. In this study, first, the modal analysis of a free-free aluminum beam was addressed in the form of three experimental, analytical, and numerical approaches. In the modal section, the dynamic responses of the beam were recorded at six points with a calibrated hammer impact test. The experimental results were combined with signal analysis and advanced algorithms to obtain modal parameters, including natural frequencies, modal vectors, and frequency responses, with an accuracy of more than 90% compared to the analytical and numerical results. Numerical modeling in Abaqus showed that the results at frequencies of 80 to 1800 Hz corresponded with acceptable accuracy and were able to simulate the vibration behavior of the system with low error. In the second section, the analysis of dynamic signs and spectral strain of the frequency response function signal was performed using wavelet transform and short-time Fourier transform methods. The results of this analysis showed that at a frequency of 255 Hz, there is a significant dynamic anomaly in mode 2 with a high quality factor (more than 25) and a strain in the range of 4.5 to 6.5, indicating the possibility of cracks, loosening, or stiffness changes in the structure. This anomaly is stable over time and is associated with mode interaction and nonlinear phenomena.

کلیدواژه‌ها English

Modal analysis
aluminum beam
spectral kurtosis
frequency response function
dynamic anomaly

اصل مقاله

[1] A. M. Fadlalla, “Modal analysis of beams using finite element methods,” Journal of Civil and Construction Engineering Research, vol. 1, no. 1, 2024, doi: 10.1007/s40567-024-00119-9.
[2] M. Avcar, “Free vibration analysis of beams considering different geometric characteristics and boundary conditions,” International Journal of Mechanical Applications, vol. 4, no. 3, pp. 94–100, 2014, doi: 10.5923/j.mechanics.20140403.03.
[3] D. H. Nguyen, L. V. Ho, T. Bui-Tien, G. De Roeck, and M. A. Wahab, “Damage evaluation of free-free beam based on vibration testing,” Applied Mechanics, vol. 1, no. 2, pp. 142–152, 2020, doi: 10.3390/applmech1020010.
[4] N. Fawazi, M. H. C. Man, and M. A. Amiruddin, “Damage detection in a free-free beam structure using reconstructed mode shape data: Experimental approach,” AIP Conference Proceedings, vol. 2798, no. 1, 2023, doi: 10.1063/5.0154234.
[5] C. C. Wu, “Study on rigid-body motions and elastic vibrations of a free–free double-tapered beam carrying any number of concentrated elements,” Journal of Vibration Engineering and Technology, vol. 10, pp. 541–558, 2022, doi: 10.1007/s42417-021-00391-x.
[6] H. Qiao, Q. S. Li, and G. Q. Li, “Vibratory characteristics of flexural non-uniform Euler–Bernoulli beams carrying an arbitrary number of spring–mass systems,” International Journal of Mechanical Sciences, vol. 44, no. 4, pp. 725–743, 2002, doi: 10.1016/S0020-7403(02)00007-3.
[7] S. Rizo-Patron and J. Sirohi, “Operational modal analysis of a helicopter rotor blade using digital image correlation,” Experimental Mechanics, vol. 56, no. 3, pp. 473–487, 2016, doi: 10.1007/s11340-016-0230-6.
[8] F. L. M. dos Santos, B. Peeters, H. Van der Auweraer, L. C. S. Goes, and W. Desmet, “Vibration-based damage detection for a composite helicopter main rotor blade,” Case Studies in Mechanical Systems and Signal Processing, 2016, doi: 10.1016/j.csmssp.2016.01.001.
[9] J. M. Montalvão e Silva and A. J. M. Araújo Gomes, “Experimental dynamic analysis of cracked free-free beams,” Experimental Mechanics, vol. 30, pp. 20–25, 1990, doi: 10.1007/BF02322697.
[10] H. Cui, X. Xu, W. Peng, Z. Zhou, and M. Hong, “A damage detection method based on strain modes for structures under ambient excitation,” Measurement, vol. 125, pp. 438–446, 2018, doi: 10.1016/j.measurement.2018.05.004.
[11] M. A.-B. Abdo and M. Hori, “A numerical study of structural damage detection using changes in the rotation of mode shapes,” Journal of Sound and Vibration, vol. 251, no. 2, pp. 227–239, 2002, doi: 10.1006/jsvi.2001.3989.
[12] F. Sayyad, B. Kumar, and S. Khan, “Approximate analytical method for damage detection in free–free beam by measurement of axial vibrations,” International Journal of Damage Mechanics, vol. 22, no. 1, pp. 133–142, 2012, doi: 10.1177/1056789512440897.
[13] H. Dai, Z. Zheng, and H. Ma, “An explicit method for simulating non-Gaussian and non-stationary stochastic processes by Karhunen–Loève and polynomial chaos expansion,” Mechanical Systems and Signal Processing, vol. 115, pp. 1–13, 2019, doi: 10.1016/j.ymssp.2018.05.026.
[14] S. Tavares, “Aircraft structural design and life-cycle assessment through digital twins,” Designs, vol. 8, no. 2, p. 29, 2024, doi: 10.3390/designs8020029.
[15] J. Li, X. Zhu, S. S. Law, and B. Samali, “Indirect bridge modal parameters identification with one stationary and one moving sensor using stochastic subspace identification,” Journal of Sound and Vibration, vol. 446, pp. 1–21, 2019, doi: 10.1016/j.jsv.2019.01.024.
[16] S. Gao, F. Liu, and C. Jiang, “Improvement study of modal analysis for offshore structures based on reconstructed displacements,” Applied Ocean Research, vol. 110, p. 102596, 2021, doi: 10.1016/j.apor.2021.102596.
[17] J. Pacheco-Chérrez and O. Probst, “Vibration-based damage detection in a wind turbine blade through operational modal analysis under wind excitation,” Materials Today: Proceedings, vol. 56, no. 1, pp. 291–297, 2022, doi: 10.1016/j.matpr.2022.01.159.
[18] X. Liu, C. Sun, J. R. Banerjee, H. C. Dan, and L. Chang, “An exact dynamic stiffness method for multibody systems consisting of beams and rigid bodies,” Mechanical Systems and Signal Processing, vol. 150, p. 107264, 2021, doi: 10.1016/j.ymssp.2020.107264.
[19] H. Salarieh and M. Ghorashi, “Free vibration of Timoshenko beam with finite mass rigid tip load and flexural–torsional coupling,” International Journal of Mechanical Sciences, vol. 48, no. 7, pp. 763–779, 2006, doi: 10.1016/j.ijmecsci.2006.01.008.
[20] S. Maiz, D. V. Bambill, C. A. Rossit, and P. A. A. Laura, “Transverse vibration of Bernoulli–Euler beams carrying point masses and considering rotatory inertia: Exact solution,” Journal of Sound and Vibration, vol. 303, nos. 3–5, pp. 895–908, 2007, doi: 10.1016/j.jsv.2006.12.028.
[21] J.-L. Dion, I. Tawfiq, and G. Chevallier, “Harmonic component detection: Optimized spectral kurtosis for operational modal analysis,” Mechanical Systems and Signal Processing, 2012, doi: 10.1016/j.ymssp.2011.07.009.
[22] B. Eftekharnejad, M. R. Carrasco, B. Charnley, and D. Mba, “The application of spectral kurtosis on acoustic emission and vibrations from a defective bearing,” Mechanical Systems and Signal Processing, vol. 25, no. 1, pp. 266–284, 2011, doi: 10.1016/j.ymssp.2010.06.010.
[23] G. M. Nita, “Spectral kurtosis statistics of transient signals,” Monthly Notices of the Royal Astronomical Society, vol. 458, no. 3, pp. 2530–2540, 2016, doi: 10.1093/mnras/stw550.
[24] M. Kiymik, I. Guler, A. Dizibuyuk, and M. Akin, “Comparison of STFT and wavelet transform methods in determining epileptic seizure activity in EEG signals for real-time application,” Computers in Biology and Medicine, vol. 35, pp. 603–616, 2005, doi: 10.1016/j.compbiomed.2004.05.001.
 

  • تاریخ دریافت 29 تیر 1404
  • تاریخ بازنگری 17 آبان 1404
  • تاریخ پذیرش 24 آبان 1404
  • تاریخ اولین انتشار 24 آبان 1404
  • تاریخ انتشار 01 بهمن 1404