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Anomalous dispersion, phase velocity increases with frequency, of longitudinal modes in five cylindrical waveguides are numerically analyzed and summarized in this paper. The aim is to study the types and characteristics of modes exhibit anomalous dispersion, and the factors affect the anomalous. The analyses results show anomalous dispersion is relative to the surface and interface waves, and it could reflect the variations of shear modulus, density, and geometric structures. [ABSTRACT FROM AUTHOR]

This paper presents the theoretical and numerical analyses of the propagation characteristics of the longitudinal modes excited by the point source in the three-layered cylindrical ultrasonic transmission rod model. The phase velocity and group velocity dispersion curves, and displacement distributions of the Stoneley mode and the quantized Stoneley mode segments are numerically simulated. The results show that the quantized Stoneley mode segments are analogous to the non-dispersive Stoneley wave propagating along the second cylindrical interface. [ABSTRACT FROM AUTHOR]

This paper presents the results from a numerical analysis of propagating guided modes along a transmission rod to aid in the design of a probe used in a liquid steel inclusion measurement system. This study investigates the effect of signal bandwidth and mode selection related to probe diameter and length on the number and types of modes. The aim is to reduce distortion and increase the signal to noise ratio of the transmitted ultrasonic signal. [ABSTRACT FROM AUTHOR]

The application of ultrasonic scattering methodologies to measure inclusions in metals in the liquid state could enable the development of techniques for understanding non-metallic particulate inclusion content or cleanliness at different process areas. The MV20/20 ultrasonic system developed for the aluminum industry has achieved some success. However, the operational temperatures evident in steel production suggest many practical issues in designing an ultrasonic measurement system due to the inability to propagate an ultrasonic pulse directly into liquid steel. This paper describes the latest developments of a novel disposable ultrasonic probe that overcomes pulse introduction difficulties as well as some of the associated issues evident in liquid steel application. A trial at the Corus pilot plant facility in the U.K shows that probe design can be used to detect backwall signals at a distance of 20 cm with a signal to noise ratio in the region of 10 dB. [ABSTRACT FROM AUTHOR]

This paper describes the application of ultrasonic scattering technologies for the development of a disposable ultrasonic probe measurement system that has the potential to (i) give size distributions for non-metallic inclusions in liquid steel and (ii) analyse relatively large volumes of liquid steel. This research demonstrates how it is possible to use the geometric condition of a dilute solution to identify a novel ultrasonic method by which 1–100 μm diameter particles can be both detected and sized. [ABSTRACT FROM AUTHOR]