Critical Aspects of Experimental Damage Detection Methodologies Using Nonlinear Vibro-ultrasonics

Dunn, Mitchell; Carcione, A.; Blanloeuil, Philippe; Veidt, Martin

doi:10.1016/j.proeng.2017.04.466

Cited by 11 publications

(20 citation statements)

References 7 publications

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“…Se han planteado diversas técnicas de detección de grietas basadas en pruebas no destructivas en materiales, aplicadas a diversas técnicas inspiradas en procesos vibratorios y fenómenos residuales como el sonido producto de desbalanceo (Dunn M. et al, 2017).…”

Section: Introductionunclassified

Propuesta de modelo de variación de consumo de corriente de un MSIP por efecto de desbalance por presencia de grietas superficiales en el rotor

Manilla-García

Cambero

Guerrero-Rodríguez

2020

Rev. iberoam. autom. inform. ind.

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<p>En el presente artículo se propone un modelo para caracterizar las variación de corriente en terminales de un motor síncrono de imanes permanentes (MSIP) como consecuencia del efecto de desbalance en el rotor a causa de una grieta superficial. Se modela el desbalance en el rotor mediante las ecuaciones de Laval con acoplamiento del efecto de la grieta superficial. Se propone un modelo de efecto de variación del entrehierro a partir de este desbalance, lo cual origina una variación en las inductancias del modelo del MSIP, que a su vez ocasionan una variación en el consumo de la corriente. Con este modelo se espera contribuir en el campo de determinación de parámetros físicos, en este caso, grietas o desbalances causados por imperfecciones que se comporten como tal.</p>

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Section: Introductionunclassified

Propuesta de modelo de variación de consumo de corriente de un MSIP por efecto de desbalance por presencia de grietas superficiales en el rotor

Manilla-García

Cambero

Guerrero-Rodríguez

2020

Rev. iberoam. autom. inform. ind.

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“…Using sidebands to detect delaminations in composite beams has been investigated by Guinto, et al (2016), Dunn, et al (2014), Dunn, et al (2016, . Through these works, the ability for the nonlinear vibro-ultrasonics to detect delaminations in composite beams has been demonstrated.…”

Section: Wave Spectroscopy Methodsmentioning

confidence: 99%

“…The sidebands within a nonlinear material are generated from inhomogeneities within the material (Dunn, et al, 2016). Consider a small crack within a material.…”

Section: Sideband Generationmentioning

confidence: 99%

Application of nonlinear vibro-ultrasonics to detect and characterise weak bonds and damage in adhesive

Josey¹

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I would like to firstly thank Dr. Martin Veidt for being my supervisor for this research. Without him I would not have been able to take part in this research. His guidance helped me stay on course and complete the research and required submissions on time. Dr. Veidt was a wonderful mentor and a great person. Our weekly meetings were always enjoyable and helpful. Alongside Dr. Veidt was the University of Queensland Composites research group. Various members of this research group, namely Alessandro Carcione, have given me small insights into other research avenues and provided their opinion on my results. Without the support of the research group and Dr. Veidt, this research and would have been much more stressful than it was. I would like to thank my friend, Mark Papinczak, for our late-night discussions where we threw ideas back and forth. These discussions helped me to understand the underlying phenomena involved with the project, as well as helping me see a fresh perspective on the results. Finally, I would like to thank my family. They had to endure my antisocial behaviour for the past 5 months where I would stay in my room all day working on this research, emerge for food, and then retire back to my room. Without their help and support, my degree would have been significantly more difficult than it was, and I am indebted to them for their love and support.

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“…Sideband ratios are rarely greater than 0.05 and can be as low as 0.0001 for weakly nonlinear systems as seen in Carcione, Blanloeuil, Rose, et al, (2019) and Dunn et al, (2017b). This can present a significant instrumentation and measurement challenge (Dunn et al, 2017b), this will be discussed in depth in the next chapter.…”

Section: Sideband Ratiomentioning

confidence: 97%

“…The sample is excited electro-mechanically at various amplitudes and frequencies between 40-70 Hz and 0.375 -3.0 V. It is observed that as the excitation amplitudes increases the peak beam deflection first shifts lower, then higher. Figure 2.13: Nonlinear resonance shifting of a beam with delamination defect (Dunn et al, 2017b) This phenomena is due to material hysteresis. When the applied excitation amplitude increases more dissipative losses are incurred and the effective modulus is decreased.…”

Section: Nonlinear Resonance Shiftmentioning

confidence: 99%

An investigation into novel techniques for nonlinear NDT measurements and their applications

Carcione¹

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Non-Destructive Testing (NDT) encompasses a diverse field of techniques that can be used to detect the presence of damage in mechanical components and parts. Among these techniques, ultrasonic pulse echo NDT is the most common method used to detect damage. Conventional ultrasonic NDT utilizes piezoelectric transducers to send and receive pulses of acoustic energy into a part. The interaction of these elastic waves with material defects can be measured as small amounts of reflected energy. However, current methods have significant limitations when it comes to defects such as micro-cracks, closed cracks or weak bonds. It is recognized that nonlinear acoustics methods can be used for the detection of early stage damage and material defects that are generally undetectable with traditional methods. One of these methods is nonlinear wave modulation also referred to as nonlinear vibro-acoustics. In this technique a sample is excited at two distinct frequencies, known as pumping and probing waves. The pumping wave is normally between 10-1000 Hz and the probing wave is in the ultrasonic range. Interactions with defects, such as cracks or weak bonds, causes intermodulation of these two frequencies due to nonlinear effects. These effects include nonlinear contact dynamics, hysteresis and contact acoustic nonlinearity (CAN). This intermodulation results in additional frequencies being present in the frequency domain that were not part of the original excitation. These new frequencies are known as sidebands or harmonics and can be directly observed by taking an FFT of the system response. This work attempts to address the disadvantages of conventional nonlinear NDT methods while also expanding the understanding of nonlinear phenomena through novel processing methods and apparatuses. In this research three novel methods have been developed. The first method utilizes nonlinear frequency mixing without requiring the use of a low frequency pumping wave. The sample is excited at several distinct but similar frequencies in the ultrasonic range using only one piezoelectric transducer. This eliminates the need of a shaker for low frequency excitation, greatly simplifying experimental design. The second technique is a novel data processing method. It is based on the down-conversion of the probing wave to recover a low frequency distorted wave, this provides a more direct and meaningful analysis of nonlinear wave modulation compared to conventional methods. This technique uses all of the sideband spectra around the probing frequency. This is in contrast to existing methods that typically only consider the first or second pair of sidebands in their analysis. Lastly, an entirely non-contact, air-coupled nonlinear vibro-acoustic measurement technique and apparatus has been developed and demonstrated. This apparatus uses non-contact ultrasonic transducers for probing wave excitation and a loudspeaker inside a resonant cavity to provide a pumping excitation. The technique is demonstrated for the detection of near surface defects for thin pl...

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Critical Aspects of Experimental Damage Detection Methodologies Using Nonlinear Vibro-ultrasonics

Cited by 11 publications

References 7 publications

Propuesta de modelo de variación de consumo de corriente de un MSIP por efecto de desbalance por presencia de grietas superficiales en el rotor

Propuesta de modelo de variación de consumo de corriente de un MSIP por efecto de desbalance por presencia de grietas superficiales en el rotor

Application of nonlinear vibro-ultrasonics to detect and characterise weak bonds and damage in adhesive

An investigation into novel techniques for nonlinear NDT measurements and their applications

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