A three dimensional computational model for evaluation of flow pattern in the main pulmonary artery

In this study, thirty methyl methacrylate casts were used to map the pulmonary artery of normal lambs, ranging in age from two to 100 days. The three-dimensional (3-D) computer tomography (CT) images of these casts were processed to extract the representative geometric parameters of the pulmonary artery. The growth pattern of the geometry of the normal pulmonary artery was analyzed by relating these parameters to age. A mathematical model was established to represent the pulmonary artery structure by a set of geometric parameters. Computer programs were developed to generate the 3-D shape of the main pulmonary artery and two daughter branches based upon the mathematical model. The finite element dynamic analysis package (FIDAP) was used to make a finite element mesh of the pulmonary artery from the generated shape. The numerical computation of the flow pattern was then carried out with a Cray Y-MP computer. The effect of the 3-D geometry on the blood flow pattern can be visualized from the result of the computation.