Papers by Keyword: Frequency Domain Fatigue

Abstract: Mechanical fatigue is an essential phenomenon that occurs when the structures are exposed to dynamic, fluctuating loadings. Especially automotive components are regularly exposed to random vibration loadings. Vibration fatigue failures may arise even in components that meet static requirements and are stable and robust, because of dynamic and fluctuating loadings. The primary focus of this study is the research of the vibration fatigue. Hence, in addition to the analyses, the tests are conducted. In order to study the analyses and tests, aluminum cross-section beams are designed and manufactured. The notched sections added to the beam geometry to acquire a more distinct fatigue life compared to other parts of the beams. The results obtained from the experimental tests are used to correlate the effect of notch parameters on fatigue life.

Abstract: Time domain approach with S-N approach and local strain approach were used for fatigue life estimation. But these days, using PSD (Power Spectral Density) method is highlighted, because of short amount of time in measurement and analysis. Especially, PSD method is useful for analysis of fatigue failure which is caused by vibration damage, also FRF (Frequency Response Function) is useful for efficient prediction of fatigue life when the same product is employing different motor vehicle or test condition. In order to estimate fatigue life of compressor for air conditioning, time domain analysis and frequency domain analysis were performed and the results were compared. As a result, results of analysis in frequency domain and time domain were similar. With this, there is recognition of decreasing the period of measuring and analysis in PSD analysis. Moreover, in case of FRF pursued of a part, using FRF is applicable at fatigue life prediction in different testing condition. There was investigated an analysis method with curtailed analysis period by FRF.