Estimation of Theoretical and Experimental Natural Frequencies of Rotating Shafts

Whirling is one of the most important things that can cause the shaft to break and the system to fail. It is generally because of the mounting of turbines, compressors, pumps, etc., on the flexible shaft, making it bend in a complicated manner. Dunkerley's empirical relation for transverse vibration of the beam is used to calculate the whirling speed of the shaft due to its self-weight. Silver steel shafts of varying diameters are used for experimental values to determine the critical speed of shafts for the first two modes for fixed–supported end conditions and the first mode for fixed–fixed end conditions. For the above analysis, ANSYS/Workbench has been used to model the same situation and obtain natural frequencies. Also, the variation of diameter on whirling speed is observed.