Paper Title
Vibration Analysis Of Propeller Shaft With Transverse Crack

Crack occurs frequently in rotating machinery due to manufacturing flaws or fatigue. These cracks affect the performance of the rotating system. If undetected, it ends in the failure of the rotating part. In propeller shafts transverse cracks occur frequently which results in the low performance and eventual failure. The purpose of this project is to identify the presence of cracks in a propeller shaft using vibrational analysis. And also the effects of cracks at different locations and crack depth at various operating angles of the cracked propeller shaft were studied. Three crack locations, three crack depth and operating angle were used in the analysis. In this work a propeller shaft connected with two universal joints was analyzed to identify the presence of transverse crack. The crack locations and crack depth were changed and the variations of the vibrational characteristics with respect to various operation angles were studied. It was observed that the decrease in the natural frequency of the system is the primary indication of the presence of crack. The natural frequency further decreases with increase in the crack depth. The presence of crack also increases the amplitude and the amplitude increases with increase in the crack depth. A second peak in the amplitude vs frequency plot rises with increase in the operating angle. These effects were interpolated by modal and harmonic analysis on the propeller shaft system. Keywords- Propeller shaft, Vibration analysis, Transverse- Crack, Frequency, Amplitude