Space-Time Characteristics of the Turbulent Flow Energy in a Viscoelastic MediumUsing Noninvasive Passive Imaging

摘要

This report describes the technology required for noninvasive passive imaging ofthe turbulent flow energy of space-time signals in a viscoelastic medium. The need for such technology emerges from the field of biomedicine, where low cost noninvasive techniques are necessary to accurately diagnose heart disease. A sensor that can detect extremely low energy levels, such as those encountered in a stenosed artery, is investigated. An experiment that consists of a urethane solid containing a partially blocked embedded surgical tube is described. Measurements of turbulence-induced energy levels are included in both the spatial-frequency domain and the wavenumber-frequency domain. Modeling of continuous sources using two different beamformers is addressed. Also presented are recommendations for future studies.