Modeling of Airflow-Based Lung Sound for Characterization of Bronchi

Abstract

An airflow-based model for studying the mapping pattern of respiratory sound spectrum and bronchi structure is introduced in this paper. Based on the three to six levels of the Weibel’s model and the theory of fluid mechanics, the transient airflow motion characteristics and the vortex motion of the lung bronchi model is simulated during the bronchial respiration, respectively. The phenomenon of vortex motion and the secondary flow caused by the shear stress of the pipe wall are further analyzed. Furthermore, based on the aeroacoustics model including large eddy simulation (LES) model combined with the FfowcsWilliams and Hawkings (FW-H) acoustic analogy model, the sound pressure level frequency curve of the sampling point at the bronchial bifurcation is achieved by simulation. Compared with the theoretical calculations, the proposed model is verified to be feasible.