PSI - Issue 39

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Nabam Teyi et al. / Procedia Structural Integrity 39 (2022) 333–346 Author na e / Structural Integrity Procedia 00 (2019) 000–000

Gómez et al., 2016

It has applications in condition monitoring under stationary conditions. Research can be undertaken for similar studies in a dynamic system. In order to identify vibration-based damage, measurement technology is largely reliant. The proposed method would be useless if it didn't have accurate vibration data. Here’s where things can be done better. Models with breathing cracks can be made using this method by substituting a breathing function in the equations. It is possible that more trials with smaller cracks be conducted in order to discover the experimentally detectable minimum crack depth using the proposed method. It is also possible to investigate how the initial fracture width affects the cracked rotor system’s dynamic behaviour.

Zhiwen Lu et al., 2016

Ebrahimi et al., 2017

Guo et al., 2017

Upadhyay and Kankar, 2017

Other bearing systems may be studied with the same model.

Zhiwen Lu et al., 2017

Validation of the proposed approach by experiments in laboratory is to be done.

Singh and Tiwari, 2018

Further research is needed to develop and validate this condensation strategy using experiments on a multi disc rotor using AMB.

Spagnol et al., 2018

The procedure may be explored for rotors with multiple cracks.

Wang et al., 2018

There are concerns with this strategy when dealing with extensive cracks because the rotor's dynamic response is no longer much smaller than the static deflection. This could be the subject of some research.

The procedure may be explored for non Jeffcott rotor systems.

Xie at al., 2018

. 5. Relevant literatures from 2019 to 2021

A novel definition of instantaneous whirling speed of axis orbit was defined by Xie et al. (2019). This new feature improved the ability to discern between regular and cracked rotor systems. The steady state vibration response of a cracked system in a Bently KR4 Rotor Test Rig was recorded. Line speed curves for normal and cracked systems were employed here. The relative whirling speed of a fractured rotor system fluctuated between two maxima and minima. The action of the extra stiffness excitation on the normal conversion of kinetic energy to potential energy induced transient change of the relative whirling speed. Hein and Jaanuska (2019) predicted an Euler–Bernoulli cantilever subjected to transverse free vibration using Haar wavelet discrete transform, ANNs and random forests. To evaluate Bayesian regularisation and the Levenberg–Marquardt algorithm, a feed-forward back propagation ANN was used. The data set of eight natural frequency factors provided better crack depth predictions, while the data set of eight Haar wavelet coefficients produced better crack location predictions. Shravankumar and Tiwari (2019) used eddy current proximity probes to investigate a transverse fatigue fracture in a universal tensile machine for fatigue loading. According to the estimates, the rigidity of the intact shaft was lowered by 0.5 percent due to the crack. AL-Shudeifat (2019) examined numerically and experimentally the produced backward whirl in intact and fractured rotor systems. The broken DDC system whirl orbits, the horizontal whirl amplitude time histories, and experimental whirl amplitudes were used. A critical forward whirl speed was reached, and then whirl amplitudes dropped fast, with further low-level transient peaks of forward whirl orbits following closely behind them. There is uncertainty in a fractured hollow-shaft rotor system, hence Fu et al. (2020) created an Uncertain Response Surrogate Function (URSF). The crack signatures for the samples were computed utilising an evolution diagram of the cracked shaft cross-section, URSF based on Chebyshev collocation points, and crack signatures with deterministic parameters. The surrogate function was accurate and resilient, allowing for an effective technique and advice for crack diagnosis in unclear situations. Using the crack-induced local distortions in multiscale SCDSs, Zhiwen Lu et al. (2020) proposed an innovative crack localization approach for stepped rotating rotors based on BF. The GSM, Teager energy operator, and BF were used to construct a new Damage Index Gaussian multiscale analysis. They used a simple rotor bearing system experiment rig, as well as an experimental rotor and sensor setup. The proposed method for single or multiple crack localization in stepped rotors proved effective, accurate, and robust, and it has a lot of practical applications. Torsional oscillation was used in an experiment conducted by Liu and Jiang (2020), who were looking