Numerical Analysis of Nasal Flow Characteristics with Microparticles

Area of Science:

• Biomedical Engineering
• Computational Fluid Dynamics
• Respiratory Science

Background:

• Understanding particle deposition in the nasal cavity is crucial for inhalation therapy and exposure assessment.
• Nasal cavity geometry and airflow dynamics significantly influence particle transport and deposition.
• Perforations in the nasal septum can alter airflow patterns and particle deposition.

Purpose of the Study:

• To investigate airflow characteristics within the nasal cavity under varying conditions.
• To analyze the impact of respiratory intensity, particle diameter, and density on nasal particle deposition.

Main Methods:

• A 3D geometric model of the nasal cavity was created from medical images.
• Computational Fluid Dynamics (CFD) using the SST k-ω turbulence model simulated airflow.
• The Lagrange discrete phase model analyzed particle deposition.

Main Results:

• Airflow through nasal septum perforations creates vortex structures, increasing particle deposition efficiencies (DE) compared to a normal nasal cavity.
• Smaller particles (≤2.5 μm) exhibited lower DE.
• Higher respiration intensity amplified the influence on larger particle DE, while particle density (>1550 kg·m⁻³) had minimal effect on 10 μm particles.

Conclusions:

• Nasal cavity perforations enhance particle deposition due to altered airflow dynamics.
• Particle size, respiration intensity, and density are key factors influencing nasal particle deposition.
• CFD modeling provides valuable insights into particle behavior within the nasal cavity.