Bir dizel gemi jeneratörünün operasyonel modal analizi

Abstract

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.

Keywords

• Operasyonel modal analiz
• jeneratör titreşimleri
• gemi titreşimleri

Operational modal analysis of a marine diesel genset

Abstract

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.

Keywords

• Operational modal analysis
• genset vibrations
• ship vibrations

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