Large eddy and detached eddy simulations of fluid flow and particle deposition in a human mouth–throat

Abstract Fluid flow was simulated in a human mouth–throat model under normal breathing conditions (30 l/min) alternatively employing RANS k – ω (without near-wall corrections), DES and LES methods. To test the validity of the fluid phase simulations, PIV measurements were carried out in a central sagittal plane of an identical model cast. Velocity and kinetic-energy profiles showed good quantitative agreement of experiments with LES/DES, and less so with RANS k – ω . Mouth–throat deposition was simulated for particle diameters 2, 4, 6, 8 and 10 μ m . By comparison with existing experimental data, LES/DES showed considerable improvement over the RANS k – ω model in predicting deposition for particle sizes below 5 μ m . For the bigger particles, RANS k – ω and LES/DES methods produced similarly good predictions. It is concluded that for the simulation of medication aerosols inhaled at a steady flow rate of 30 l/min, LES and DES provide more accurate results than the RANS k – ω model tested.

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