Abstract

Dr Valerie Pinfield (Loughborough University) and Prof Megan Povey (University of Leeds) Mathematical theories of multiple wave scattering of necessity make simplifications and assumptions in order to render a system tractable. For example, we might construct a semi-infinite half-space with randomly distributed identical point scatterers. In reality, however, we want to use multiple wave scattering theories to enable us to investigate rather more complex systems than these simplified theoretical propositions. Here we present the use of ultrasonic measurements to explore the properties of complex materials such as emulsions, suspensions of solid particles, and crystallising fats or pharmaceutical ingredients. We will show how multiple wave scattering theories can be used to interpret experimental measurements and their power in studying system behaviour. We will highlight some of the differences between the theoretical constructs of scattering models and experimental reality, for example the use of a finite source, a finite system (boundaries), finite signal duration, time-averaging, spatial averaging and phase sensitivity of the detector amongst others.