The partial differential equation for the wave function in the problem of the diffraction of light by an ultrasonic wave is derived as the result of transformations and related approximations of the electrical field equation itself. It is shown that this way of treating the diffraction problem is equivalent to the generating function method applied to the Raman-Nath system of difference-differe...

The use of numerical and phased array techniques to focus guided waves and perform inspection of plates and pipes has not been widely used; it represents an interesting solution for defect detection and localization. In addition, imaging of ultrasonic guided wave results using color coded B-Scans is also considered a highly valuable tool for data interpretation. While commercial ultrasonic phas...

Nondestructive evaluation (NDE) of aerospace structures using traditional methods is a complex, time-consuming process critical to maintaining mission readiness and flight safety. Limited access to corrosion-prone structure and the restricted applicability of available NDE techniques for the detection of hidden corrosion or other damage often compound the challenge. In this paper we discuss our...

Compared with conventional linear ultrasonic inspection methods, which are sensitive only to severe defects, nonlinear ultrasonic inspection methods are better for revealing micro-cracks in thin plates. However, most nonlinear ultrasonic inspection methods have only been experimentally investigated using bulk or Rayleigh waves. Numerical studies, especially numerical simulations of Lamb ultraso...

The properties of ultrasonic creeping wave were stated. Experimentations on the rabbet of aeroengine turbine blade were applied with ultrasonic creeping wave testing. The result indicates that the creeping testing method is feasible to inspect the rabbet of turbine blade in situ.

In this paper, the reflection of ultrasonic guided waves from simple dent in pipes has been investigated using finite element method and the relationship between reflection coefficient of these waves and deformation rate has been determined. Also, the effect of the parameters of wave generation source on the generated wave field has been investigated using normal modes expansion method. At firs...

Methods of measuring ultrasonic wave velocity in an elastic sample require data on the thickness of the sample and/or the distances between the transducers and the sample. The uncertainty of the ultrasonic wave velocity measurements generally depends on that of the data available. Conversely, to determine the thickness of a material, it is necessary to have a priori information about the wave v...

Ultrasonic tissue characterization has shown promise for clinical diagnosis of diseased bone (e.g., osteoporosis) by establishing correlations between bone ultrasonic characteristics and the state of disease. Porous (trabecular) bone supports propagation of two compressional modes, a fast wave and a slow wave, each of which is characterized by an approximately linear-withfrequency attenuation c...

The stress on a test specimen during tensile testing is generally measured by a strain gauge. This method has some problems in that it would influence the measurement conditions of the tensile test and can evaluate only the position at which the strain gauge is attached. The acoustoelastic method is proposed as a method replacing the strain gauge method. However, an ultrasonic sensor with a pie...