Dry powder inhalers, or DPIs, are becoming indispensable tools for treating pulmonary conditions because they reliably deliver medication straight to the lungs. The effectiveness of these devices depends on the delicate interactions between particle behavior and airflow dynamics inside the human respiratory system. In order to improve drug delivery efficiency and optimize DPI design, which will ultimately improve the treatment outcomes for millions of patients worldwide suffering from respiratory illnesses, it is imperative to comprehend these airflow structures and their impact on particle deposition. This study relies on a valid reference paper titled “ Dry Powder Inhaler Aerosol Deposition in a Model of Tracheobronchial Air‐ ways: Validating CFD Predictions with In Vitro Data”.

Figure 1: Airway model (reference paper)

Simulation Process

Due to the complex geometry of the human tracheobronchial airways, it seems necessary to utilize an appropriate numerical approach to capture the airflow structures. Fluent Meshing meshes the airway of the lungs via 4194488 polyhedral cells. Given the presence of a dry powder inhaler, the problem of the Eulerian-Lagrangian approach was solved. Thus, Discrete Phase Model (DPM) activation is inevitable. However, to include their harmful effects on the lung walls, the Erosion/Accretion sub-model is also activated.

Post-processing

The intricate details of airflow dynamics and particle behavior essential for enhancing pulmonary drug delivery are revealed by the CFD simulations of dry powder inhalers in human lungs. There are differences in the wall shear stress distribution along the airways, with increased stress along airway bends and at bifurcations. Despite being usually modest across much of the airway surface, particle accretion rates show discrete hotspots in the trachea and at branching sites. These results are consistent with the turbulence initiation, reverse flow, vortex generation, and extrathoracic laryngeal jet observations. Millions of patients with respiratory disorders will benefit from improved DPI design and improved therapy outcomes if these complex flow patterns and their effects on particle deposition are better understood. The simulations offer insightful information on the variables influencing drug delivery effectiveness, which may result in pulmonary disease therapies that are more efficacious.