Comparative analysis of airflow dynamics and sputum expulsion during cough in healthy and bronchial stenosis respiratory tract.

Bronchial stenosis impacts cough mechanisms and respiratory function. This study used MIMICS and Fluent to construct and simulate a 3D airway model of an elderly female patient with bronchial stenosis. Utilizing dynamic mesh and fluid-structure interaction, airflow during coughing was analyzed, including velocity, wall shear stress, and deformation. The Eulerian wall film model quantified sputum dynamics, revealing that stenosis increases shear stress, exacerbates deformation, and reduces sputum expulsion efficiency, particularly for medium to high viscosity sputum. These findings deepen understanding of bronchial stenosis pathophysiology and offer insights for improving diagnosis, treatment, and prevention of respiratory diseases.