Characterisation of dynamic rough surfaces through airborne acoustic scattering
Dr Giulio Dolcetti
University of Trento, Department of Civil, Environmental and Mechanical Engineering
Characterisation of dynamic rough surfaces through airborne acoustic scattering: theory, methods, and applications for non-contact river monitoring
Abstract:
Historically, the mapping and/or monitoring of geophysical surfaces based on airborne wave scattering has been a prerogative of electromagnetics, while acoustic applications have been typically confined to underwater or underground environments. However, acoustics hold significant potential for airborne applications particularly on small-to-medium scales, due to relatively low costs, compact size, and flexible deployment options. In this talk, I will retrace the steps that led to some of the latest advancements in rough surface characterisation using airborne acoustic scattering. I will give a brief introduction of the theory based on the Kirchhoff and small perturbation approximations, which is key to interpreting the results and quantifying errors and resolution. I will compare various implementation approaches using different setups, geometries, and signals. Finally, I will discuss some applications for the reconstruction of the shape and dynamics of water waves on the surface of turbulent flows and rivers, demonstrating how key principles and methods of physical acoustics can offer fresh insights into complex phenomena in seemingly unrelated fields, such as hydraulics.