Across nondestructive testing and structural health monitoring (SHM), accurate knowledge of the systems’ reliability for detecting defects, such as probability detection (POD) analysis is essential to enabling widespread adoption. Traditionally, this relies on access extensive experimental data cover all critical areas parametric space, which becomes expensive, heavily undermines benefit systems bring. In response these challenges, estimation based numerical simulation emerges a practical...

Fatigue zones in a material can be identified using ultrasonic waves, as it has been shown that their propagation speed will reduce when travelling through such zone. However, fatigue damage is usually concentrated thin near-surface layer, through-thickness measurements result very small changes of the average across full thickness, which are potentially difficult to reliably correlate specific states. In this study, we have completed state assessments Rayleigh travel on surface material,...

Rayleigh waves are well known to attenuate due scattering when they propagate over a rough surface. Theoretical investigations have derived analytical expressions linking the attenuation coefficient statistical surface roughness parameters, namely, surface's root mean squared height and correlation length wave's wavenumber. In literature, three regimes been identified—the geometric (short wavelength), stochastic medium (long wavelength) regimes. This study uses high-fidelity two-dimensional...

The phenomenon of Rayleigh wave attenuation due to surface roughness has been well studied theoretically in the literature. Three scattering regimes describing it have identified—the (long wavelength), stochastic (medium and geometric (short wavelength)—with coefficient exhibiting a different behavior each. Here, an extension our previous work, we gain further insight with regard existing theory, three dimensions, using finite element (FE) modeling, under unified approach, where same FE...

Across non-destructive testing (NDT) and structural health monitoring (SHM), accurate knowledge of the systems' reliability for detecting defects, such as Probability Detection (POD) analysis is essential to enabling widespread adoption. Traditionally this relies on access extensive experimental data cover all critical areas parametric space, which becomes expensive, heavily undermines benefit systems bring. In response these challenges, estimation based numerical simulation emerges a...

The behaviour of the attenuation coefficient Rayleigh waves, when they propagate over surfaces which are not smooth, has been well-studied in literature. This scattering is generally split into three regimes, based on comparative size wavelength to rough surface profile; those (long wavelength), stochastic medium wavelength) and geometric (short regimes. Here, an extension our previous work, we validate existing theory, dimensions. achieved using finite element (FE) modelling under a unified...

The phenomenon of the reduction in propagation speed an ultrasonic wave when it travels through a fatigue zone has been well studied literature. Additionally, established that shear waves are more severely affected by presence such zone, compared with longitudinal waves. Our study utilises these phenomena to develop method able characterise state steel pipes. Initially, existing theory regarding increased sensitivity is validated measuring and comparing change both bulk on flat geometries,...