Showing papers by "A. S. Sekhar published in 2019"
TL;DR: In this article, the analytical formulations for dynamic analysis of composite tube shafts are mainly equivalent to the ones used in this paper, and they are used for composite materials having good dynamic properties, specific strength and specific stiffness.
Abstract: Composite materials are having good dynamic properties, specific strength, and specific stiffness. The analytical formulations for dynamic analysis of composite tube shafts are mainly equivalent mo...
8 citations
05 Nov 2019
TL;DR: In this paper, the spectral kurtosis (SK) and fast kurtogram were used to detect the fatigue cracks in rotating machinery components like shafts subjected to continuous fluctuating loads.
Abstract:
Rotating machinery components like shafts subjected to continuous fluctuating loads are prone to fatigue cracks. Fatigue cracks are severe threat to the integrity of rotating machinery. Therefore it is indispensable for early diagnostics of fatigue cracks in shaft to avoid catastrophic failures. From the literature, it is evident that the spectral kurtosis (SK) and fast kurtogram were used to detect the faults in bearings and gears. The present study illustrates the use of SK and fast kurtogram for early fatigue crack detection in the shaft using vibration data. To perform this study, experiments are conducted on a rotor test rig which is designed and developed according to the function specification proposed by ASTM E468-11 standard. Fatigue crack is developed, on three shaft specimens, each seeded with the same circumferential V-Notch configuration, by continuous application of stochastic loads on the shaft using electrodynamic shaker in addition to the unbalance forces that arise in normal operating conditions. Vibration data is acquired from various locations of the rotor, using different sensors like miniature accelerometers, laser vibrometer and wireless telemetry strain gauge, till the shaft specimen develops fatigue crack. The analysis results show that the combination of SK and fast kurtogram is an effective signal processing technique for detecting the fatigue crack in the shaft.
3 citations
01 Jun 2019
TL;DR: In the present study, optimum design parameters of a rotor-bearing system are found by employing multiple multiobjective optimization schemes for simultaneously minimizing unbalance response, maximizing stability limit speed, and minimizing system weight.
Abstract: With ever-increasing demand for higher flexibility and higher speeds of operation of high-speed rotating machinery, study of their unbalance responses and stability are of paramount importance. For...
1 citations