A New Fault Diagnosis Approach for Heavy-Duty Gas Turbines

Objective: In order to diagnose the analog circuit fault correctly, an analog circuit fault diagnosis approach on basis of wavelet-based fractal analysis and multiple kernel support vector machine (MKSVM) is presented in the paper. Methods: Time responses of the circuit under different faults are measured, and then wavelet-based fractal analysis is used to process the collected time responses for the purpose of generating features for the signals. Kernel principal component analysis (KPCA) is applied to reduce the features’ dimensionality. Afterwards, features are divided into training data and testing data. MKSVM with its multiple parameters optimized by chaos particle swarm optimization (CPSO) algorithm is utilized to construct an analog circuit fault diagnosis model based on the testing data. Results: The proposed analog diagnosis approach is revealed by a four opamp biquad high-pass filter fault diagnosis simulation. Conclusion: The approach outperforms other commonly used methods in the comparisons.

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Generative Oversampling and Deep Forest based Minority-class Sensitive Fault Diagnosis Approach

2020 IEEE International Conference on Systems, Man, and Cybernetics (SMC) ◽

10.1109/smc42975.2020.9283190 ◽

2020 ◽

Author(s):

Huifang Li ◽

Rui Fan ◽

Qisong Shi

Keyword(s):

Fault Diagnosis ◽

Minority Class ◽

Deep Forest ◽

Diagnosis Approach

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Investigation of Failure in Gas Turbines: Part 2 — Engineering and Metallographic Aspects of Failure Investigation

Volume 2: Combustion and Fuels; Oil and Gas Applications; Cycle Innovations; Heat Transfer; Electric Power; Industrial and Cogeneration; Ceramics; Structures and Dynamics; Controls, Diagnostics and Instrumentation; IGTI Scholar Award ◽

10.1115/93-gt-084 ◽

1993 ◽

Author(s):

Robert E. Dundas

Keyword(s):

Gas Turbine ◽

Gas Turbines ◽

Heavy Duty ◽

Metallographic Examination ◽

Fracture Surfaces ◽

Failure Investigation ◽

Materials Used ◽

Component Failures

This paper opens with a discussion of the various mechanisms of cracking and fracture encountered in gas turbine failures, and discusses the use of metallographic examination of crack and fracture surfaces. The various types of materials used in the major components of heavy-duty industrial and aeroderivative gas turbines are tabulated. A collection of macroscopic and microscopic fractographs of the various mechanisms of failure in gas turbine components is then presented for reference in failure investigation. A discussion of compressor damage due to surge, as well as some overall observations on component failures, follows. Finally, a listing of the most likely types of failure of the various major components is given.

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A Rolling Element Bearing Fault Diagnosis Approach Based on Multifractal Theory and Gray Relation Theory

PLoS ONE ◽

10.1371/journal.pone.0167587 ◽

2016 ◽

Vol 11 (12) ◽

pp. e0167587 ◽

Cited By ~ 10

Author(s):

Jingchao Li ◽

Yunpeng Cao ◽

Yulong Ying ◽

Shuying Li

Keyword(s):

Fault Diagnosis ◽

Relation Theory ◽

Rolling Element Bearing ◽

Bearing Fault ◽

Bearing Fault Diagnosis ◽

Rolling Element ◽

Multifractal Theory ◽

Element Bearing ◽

Diagnosis Approach

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Development and Validation of a Three-Dimensional Multiphase Flow CFD Analysis for Journal Bearings in Steam and Heavy Duty Gas Turbines

Volume 7: Structures and Dynamics, Parts A and B ◽

10.1115/gt2012-68201 ◽

2012 ◽

Cited By ~ 2

Author(s):

Stephan Uhkoetter ◽

Stefan aus der Wiesche ◽

Michael Kursch ◽

Christian Beck

Keyword(s):

Experimental Data ◽

Multiphase Flow ◽

Gas Turbines ◽

High Speed ◽

Three Dimensional ◽

Air Entrainment ◽

Journal Bearings ◽

Heavy Duty ◽

Present Contribution ◽

Two Phase

The traditional method for hydrodynamic journal bearing analysis usually applies the lubrication theory based on the Reynolds equation and suitable empirical modifications to cover turbulence, heat transfer, and cavitation. In cases of complex bearing geometries for steam and heavy-duty gas turbines this approach has its obvious restrictions in regard to detail flow recirculation, mixing, mass balance, and filling level phenomena. These limitations could be circumvented by applying a computational fluid dynamics (CFD) approach resting closer to the fundamental physical laws. The present contribution reports about the state of the art of such a fully three-dimensional multiphase-flow CFD approach including cavitation and air entrainment for high-speed turbo-machinery journal bearings. It has been developed and validated using experimental data. Due to the high ambient shear rates in bearings, the multiphase-flow model for journal bearings requires substantial modifications in comparison to common two-phase flow simulations. Based on experimental data, it is found, that particular cavitation phenomena are essential for the understanding of steam and heavy-duty type gas turbine journal bearings.

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