The characterisation of multicomponent (liquid) flows using scattered ultrasound.

The aim of this work is to determine the applicability of ultrasonic techniques to developing a non invasive flow meter capable of characterising multicomponent (liquid) flows. The possibility of detecting flow parameters such as velocity distributions, droplet/particle size distributions, spatial distribution and void fraction of the discontinuous phase has been investigated. An early consideration of the likely applications of this meter, revealed that an ultrasonic technique would be the most versatile and suitable. Consequently, a theoretical study of the interaction of an ultrasonic wave and a disperse system has been carried out, as well as a study of the possible regimes where these principles may be applied. The work begins from first principles, studying both experimentally and theoretically the interaction of an acoustic wave with a single particle. This is then extended to characterising a flowing multicomponent system on a larger scale. The nature of complex flows was then investigated from the point of view of a chaotic dynamical system. Both theoretical and experimental methods show this to be a valid approach to understanding the flow of mixtures.