Gas Transport in Human Lungs - Modelling and Simulation

摘要

The external respiratory functions and basic pneumatic mechanisms in the human respiratory system are incorporated into mathematical model of gas transport problems, which presents a possible solution of the dynamic variety of a gas pressures and flows in pulmonary airways under definite conditions. The governing differential equations of aerodynamics were appropriately simplified as one-dimensional and time-variant, mixing effects at the bifurcations were neglected, the transpul-monary pressure was sinusoidal and the alveolar volume was filling and emptying as an elastic pneumatic "reservoir" created ventilation of the bronchial tree. The lungs were represented by the network of bifurcations of tree system encompassed up to 24 generations. The results indicated that the time dependent pressure gradient and flow rate for each generation yield information in two levels, i.e. local distribution and global transmission.