Multi-bifurcation flow analysis on 2D human respiratory airway system

Drug inhalation through respiratory airway is the principal method in attaining therapeutic effect for many lung diseases. The multi-bifurcating flow structure acquires deep understanding on the flow driven transportation. This work employs Navier-Stokes equation with Splitting Method numerical flow solver utilizing domain characterization technique. Various breathing conditions are commenced to Weibel´s morphometric lung model from fifth to seventh generations of human respiratory system. Velocity distributions, vortex formations and cross-sectional velocity profiles are considered for Reynolds number ranging from resting to moderate exercise breathing. Flow with low Reynolds number retains its symmetric cross-sectional velocity profile across each bifurcation region while higher Reynolds number shows the other way. Drug delivery efficacy is higher with slower inhalation while hard breathing stimulates vortex formations and disturbs drug distributions right through the multi-bifurcation structure.