An acoustic boundary element (BE) model for porous compliant material like the lung parenchyma is developed and validated theoretically and experimentally. This BE model is coupled with a source localization algorithm to predict the position of an acoustic source within a lung phantom. The BE model is also coupled with a finite element (FE) model to simulate the surrounding shell-like chest wall. Experimental studies validate the BE-based source localization algorithm and show that the same algorithm fails if the BE simulation is replaced with a free field assumption that neglects reflections and standing wave patterns created within the finite-size lung phantom. This research is relevant to the development of advanced auscultatory techniques for lung, vascular and cardiac sounds within the torso that utilize multiple noninvasive sensors to create acoustic images of the sound generation and transmission to identify certain pathologies.

Volume Subject Area:
Bioengineering
Topics:
Acoustics, Lung, Algorithms, Phantoms, Boundary element methods, Finite element analysis, Reflection, Sensors, Shells, Simulation, Standing waves
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