Bir dizel gemi jeneratörünün operasyonel modal analizi

Öz

Bu çalışmada, özellikle ikaz kuvvetlerinin belli olmadığı durumlarda, yapıların, çalışma şartlarında modal karakteristiklerinin elde edilmesi amacıyla geliştirilmiş bir deneysel modal analiz yöntemi olan Operasyonel Modal Analiz (OMA) yönteminin bir dizel gemi jeneratör seti üzerinde uygulanması gerçekleştirilmiştir. Çalışmada, modal analizi yapılan jeneratör setinin, kaidelerinden sökülmeden ve herhangi bir ikaz vermeden, çalışma esnasında titreşim zaman veri setleri kaydedilmiş ve güç spektral yoğunlukların tekil değerlere ayrıştırılması yöntemi ile harmonikler ve doğal frekans değerleri elde edilmiştir.

Anahtar Kelimeler

• Operasyonel modal analiz
• jeneratör titreşimleri
• gemi titreşimleri

Operational modal analysis of a marine diesel genset

Öz

In this study, one of the experimental modal analysis methods called Operational Modal Analysis (OMA) which is conducted in order to obtain modal characteristics of a running system when the excitation forces are unknown and the system is in ambient conditions, has been applied on a marine diesel generator set. In the study, the vibration time datasets have been recorded without detaching the genset from the foundations in ambient conditions and the modal frequencies with harmonics have been obtained using the method of singular values decomposition of power spectral densities.

Anahtar Kelimeler

• Operational modal analysis
• genset vibrations
• ship vibrations

Kaynakça

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4. Yang, Y. ve Nagarajaiah, S., Output-only modal identification with limited sensors using sparse component analysis, Journal of Sound and Vibration, 332, 19, 4741-4765, (2013).
5. Brincker, R., Zhang, L. ve Andersen, P., Modal identification of output-only systems using frequency domain decomposition, Smart Materials and Structures, 10, 3, 441-445, (2000).
6. Brincker, R., Some elements of operational modal analysis, Proceedings, International Conference on Structural Engineering Dynamics, 2014, (2013).
7. Grosel, J., Sawicki, W. ve Pakos, W., Application of classical and operational modal analysis for examination of engineering structures, Procedia Engineering, 91, 136-141, (2014).
8. Carden, E. P. ve Lindblad, M., Operational modal analysis of torsional modes in rotating machinery, The Journal of Engineering for Gas Turbines and Power, 137, 2, (2015).

9. Johansson, J., Samuelsson, H., Jacobsen, N. J. ve Angantyr, A., Operational modal analysis of large 2-pole rotating machinery, Proceedings, 3rd lnternational Operational Modal Analysis Conference, Portonovo, Italy, (2009).
10. Carden, E. P., Investigation of offshore diesel generator failure using operational modal analysis, Proceedings, 5th International Operational Modal Analysis Conference, Guimarães, Portugal, (2013).
11. Bednarz, J., Example of the application of operational modal analysis method for damage detection of the rotating blades, Vibroengineering Procedia, 6, 45-49, (2015).