Um modelo genérico para fluxos em estruturas auto-similares e a sua relação com espectros afins: da geometria da árvore brônquica às características dos sons pulmonares.

Abstract

In this work, a theoretical scheme is considered for normal lung sound pro-

duction in high frequencies. This scheme is based on multi-scaled _ux discretiza-

tion into independent discrete elements, which interact with the geometric struc-

ture that represents the bronchial tree in a syntonized fashion. The resulting

amplitude spectrum is a_ne in a log-log scale with slope dependence on the frac-

tal dimension of the bronchial tree. The results from a theoretical analysis of this

scheme is compatible, qualitatively and quantitatively with the spectral characte-

ristics reported in the literature.

Furthermore, a computational and simulational model is realized starting

from the theoretical scheme. Moreover, the computational model extends the the-

oretical scheme introducing interactions among the discrete elements by potentials.

These interactions yield a more precise adjustment of the spectra in low frequency

as well as in the high frequency spectral region.

Finally, a sound synthesis method is