Knowledge extraction to automate CFD analysis in abdominal aneurysm diagnosis and treatment

In the last few years, advanced simulation tools have been tested in academic researches to evaluate the causes and evolution of abdominal aortic aneurysm AAA. This study describes the activity of knowledge extraction aimed at automating the CFD analysis of an AAA. A simple benchmark geometry is considered. Knowledge and rules extraction are done by comparing: 2D and 3D CFD solutions, results from Newtonian and non-Newtonian formulations, influence of the prism layer and inlet boundary conditions, and numerical solver schemes. A grid refinement study using the verification and validation approach was done. As a result, finer hexahedral meshes with a prism layer near the vessel walls is necessary to capture the velocity gradient and wall shear stress correctly; a simple Newtonian formulation is enough to capture the fluid flow behaviour. A first step in the validation process is taken through the application of the extracted rules on a real patient's specific geometries.