Establishing a Baseline CFD Model for Examining Benefits of High-Flow Nasal Cannula Oxygen Therapy*

High-flow nasal cannula oxygen therapy is a type of respiratory therapy that supplies oxygen to the body at high flow rates using a specific nasal cannula. Quantitative data describing the benefit that this therapy provides is still lacking within literature. The aim of this study is to create a baseline model that can be used for computational fluid dynamic (CFD) analysis using different cannulas and flow settings. The geometry analyzed is a partial representation of the human respiratory system. The meshing methods and quality validation are outlined. The process of establishing proper boundary conditions and solver settings for the model are discussed. After the initial model was finalized, the type and location of data to be collected was decided. Some of the data collected includes mole fraction O₂, turbulent kinetic energy, and volume flow rate. Mesh and time step independence studies were conducted during the validation process. The final mole fraction O₂ of the CFD model is 0.4 percentage points different than the experimental value. Further research for this topic includes introducing CO₂ into the boundary conditions and evaluating flush using different cannula and flow settings.