Identification of Asynchronous Blade Vibration Parameters by Linear Regression of Blade Tip Timing Data

Bastami, Abbas Rohani; Safarpour, Pedram; Mikaeily, Arash; Mohammadi, Mohammad

doi:10.1115/1.4038880

Cited by 28 publications

(8 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…They also proposed a particular placement of optical laser probes in the case of shrouded bladed disk. Bastami et al 10 applied the least mean square algorithm to identify frequency and amplitude of vibration of a single-bladed experimental model in a test rig. Hajnayeb et al 11 proposed a new low-cost blade tip-timing test setup for simulating blade vibrations, based on kinematic inversion.…”

Section: Introductionmentioning

confidence: 99%

A new bladed assembly simulator and an improved two-parameter plot method for blade tip-timing numerical simulations

Nikpour

Moradi

Soodmand

2021

Proceedings of the Institution of Mechanical Engineers, Part G:

View full text Add to dashboard Cite

The blade tip-timing measurement technique is presently the most promising technique for monitoring the blades of axial turbines and aircraft engines in operating conditions. Due to the high cost of experimental simulations of blade tip-timing–based condition monitoring methods, a numerical simulator for the vibrational behavior of bladed assemblies can be helpful for researchers interested in this field. So far, in most of the numerical simulators, the centrifugal effect of rotational speed on the natural frequencies is neglected. In this study, a new bladed assembly considering the centrifugal effect of the rotational speed for blade tip-timing numerical simulations is proposed. Moreover, an improvement in the engine order estimation algorithm in a two-parameter plot method is accomplished. In the assembly, blades are assumed to be cantilevered Euler–Bernoulli beams coupled together using linear springs. The finite element method is used to extract mass and stiffness matrices from differential equations of the system. By using the two-parameter plot method, the engine order of the excitation is detected. To examine the performance of the algorithm, Monte–Carlo simulation is implemented. The new simulator fulfills both cyclic symmetry and increase in the natural frequencies with increase in rotational speed. Engine order estimation with the new formulation in the two-parameter plot method is accurate. Hence, the new simulator and formulation for two-parameter plot method are reliable for numerical simulations.

show abstract

Section: Introductionmentioning

confidence: 99%

A new bladed assembly simulator and an improved two-parameter plot method for blade tip-timing numerical simulations

Nikpour

Moradi

Soodmand

2021

Proceedings of the Institution of Mechanical Engineers, Part G:

View full text Add to dashboard Cite

show abstract

“…A significant number of papers, introducing new BTT models and algorithms such as a new two-parameter plot method [17], convolutional neural networks [18], aliasing reduction [19,20], sparse representation and compressed sensing [21] were published recently, but they can be applied in real life to a limited extent. Several newly introduced algorithms work well only with simulated or rig acquired data, usually with a single response of the first mode.…”

Section: Introductionmentioning

confidence: 99%

Non-Contact Measurement of Blade Vibration in an Axial Compressor

Przysowa¹,

Russhard²

2019

Preprint

View full text Add to dashboard Cite

Complex blade responses such as a rotating stall or simultaneous resonances are common in modern engines and their observation can be a challenge even for state-of-the-art tip-timing systems and trained operators. This paper analyses forced vibrations of axial compressor blades, measured during the bench tests of the SO-3 turbojet. In relation to earlier studies conducted in ITWL with a small number of sensors, a multichannel tip-timing system let us observe simultaneous responses or higher-order modes. To find possible symptoms of a failure, blade responses in a healthy and unhealthy engine configuration with an inlet blocker were studied. The used analysis methods covered all-blade spectrum and the circumferential fitting of blade deflections to the harmonic oscillator model. The proposed modal solver can track the vibration frequency and adjust the engine order on the fly. That way, synchronous and asynchronous vibrations are observed and analysed together with an extended variant of least squares. The proposed approach helps to avoid common mistakes and saves a lot of work related to configuring the conventional solver.

show abstract

“…Lawson and Ivey proposed measuring blade vibration amplitude through dual capacitance probe tip timing [ 14 ]. Bastami et al used two BTT sensors to identify the frequency and amplitude of asynchronous blade vibration by using the least mean square algorithm [ 15 ]. Dimitriadis et al studied the effects of the various dynamic phenomena during synchronous vibrations on the BTT technique itself and pointed out that there is no single BTT data analysis method to address all these phenomena [ 16 ].…”

Section: Introductionmentioning

confidence: 99%

Reconstructed Order Analysis-Based Vibration Monitoring under Variable Rotation Speed by Using Multiple Blade Tip-Timing Sensors

Chen

Liu

Zhan

et al. 2018

Sensors

View full text Add to dashboard Cite

On-line vibration monitoring is significant for high-speed rotating blades, and blade tip-timing (BTT) is generally regarded as a promising solution. BTT methods must assume that rotating speeds are constant. This assumption is impractical, and blade damages are always formed and accumulated during variable operational conditions. Thus, how to carry out BTT vibration monitoring under variable rotation speed (VRS) is a big challenge. Angular sampling-based order analyses have been widely used for vibration signals in rotating machinery with variable speeds. However, BTT vibration signals are well under-sampled, and Shannon’s sampling theorem is not satisfied so that existing order analysis methods will not work well. To overcome this problem, a reconstructed order analysis-based BTT vibration monitoring method is proposed in this paper. First, the effects of VRS on BTT vibration monitoring are analyzed, and the basic structure of angular sampling-based BTT vibration monitoring under VRS is presented. Then a band-pass sampling-based engine order (EO) reconstruction algorithm is proposed for uniform BTT sensor configuration so that few BTT sensors can be used to extract high EOs. In addition, a periodically non-uniform sampling-based EO reconstruction algorithm is proposed for non-uniform BTT sensor configuration. Next, numerical simulations are done to validate the two reconstruction algorithms. In the end, an experimental set-up is built. Both uniform and non-uniform BTT vibration signals are collected, and reconstructed order analysis are carried out. Simulation and experimental results testify that the proposed algorithms can accurately capture characteristic high EOs of synchronous and asynchronous vibrations under VRS by using few BTT sensors. The significance of this paper is to overcome the limitation of conventional BTT methods of dealing with variable blade rotating speeds.

show abstract

Identification of Asynchronous Blade Vibration Parameters by Linear Regression of Blade Tip Timing Data

Cited by 28 publications

References 17 publications

A new bladed assembly simulator and an improved two-parameter plot method for blade tip-timing numerical simulations

A new bladed assembly simulator and an improved two-parameter plot method for blade tip-timing numerical simulations

Non-Contact Measurement of Blade Vibration in an Axial Compressor

Reconstructed Order Analysis-Based Vibration Monitoring under Variable Rotation Speed by Using Multiple Blade Tip-Timing Sensors

Contact Info

Product

Resources

About