Local vs. global parameters in case of grid-sensitivity study for computational fluid dynamics with application in bypass hemodynamics

Abstract

Computational fluid dynamics is a non-invasive in silico tool, useful for a detailed analysis of blood flow through the cardiovascular system, especially in coronary flow. The accuracy of numerical results is strongly dependent on the grid used for geometry meshing. A fine mesh is supposed to provide accurate data useful for medical applications in diagnosis, monitoring or prediction of patient evolution in coronary bypass surgery. The efficiency of a fine mesh could be analyzed regarding local or global hemodynamic parameters associated with the flow through the vascular investigation segment. This paper analyzes the influence of some cells and the presence of boundary layer in mesh configurations to the evolution of local hemodynamic parameters (length of recirculation regions in the vicinity of anastomosis region, maximum values of Wall Shear Stress) and global parameter (pressure drop). The use of a fine mesh increases the accuracy of local parameters, offering a better understanding of the local hemodynamics in regions of interest.