Fluid Flow and Particle Deposition Simulations in the Human Nose

In this work, the aerodynamics and particle flow patterns in the human nose are simulated by Computational Fluid Dynamics (CFD). The simulations were carried out by use of Fluent, and the volume grid was generated by Tgrid. To be able to perform successful CFD-calculations of the nose, construction of a proper surface grid of the nasal cavity was mandatory. A high resolution CT-scan was the first part of this process, whereafter the 3-dimensional surface geometry was created by a pipeline of image segmentation andgeometric modification steps. The work described in this paper was initiated by a Norwegian company (OptiNose AS) developing a patented concept for efficient nasal delivery of drugs and vaccines. The objective of the article is to show how CFD can be applied as a tool to visualize and demonstrate the basic features of this technique and how it can be used to further optimize design and function of novel delivery devices based on the bi-directional concept. It is worth of notice, that the complexity of the nasal airway represents considerable challenges for CFD computations. This article shows, however, promising results on the issue. The simulations in Fluent are carried out with a reasonable range of flow rates and particle sizes typical to nasal delivery.