Experimental and numerical investigation of patient-specific hemodynamics in the thoracic aorta using the CFD method with Newtonian blood flow assumption

Abstract

Researchers widely conduct numerical studies of aortic flows. Computational fluid dynamics (CFD) is a method used to guide blood flow in vascular flows. Multidisciplinary studies are undertaken to assess vascular flow from an engineering and medical perspective. In this study, blood flow in the aorta is investigated using magnetic resonance (MR) or computed tomography (CT) angiographic images obtained retrospectively from a healthy individual, and the images are segmented with support from the surgical team to create 3D models. The segmented 3D aortic model is produced by additive manufacturing. A mixture of glycerol-purified water is prepared for blood under Newtonian blood flow conditions. Viscosity and density are measured in the laboratory at body temperature. Flow rate and pressure variations at the aortic inlet, descending aorta, and three main branches of the aorta were obtained with experimental and numerical methods using flow meters and pressure transmitters. The study is also performed numerically, and the experimental results are compared with the numerical analyses. The relative error between the experimental and numerical results does not exceed 10%, except for some turbulence models used for this study, for the flow rate and pressure along the cardiac cycle. The laminar and shear stress transport (SST) k–ω turbulence models showed good agreement with experimental studies. The deviations in mass flow rate and pressure are nearly 8 and 7%, respectively, between the experimental and numerical studies conducted using SST-k–ω turbulence models, both assuming laminar flow. This study has provided the opportunity to examine different parameters in aortic studies. Additionally, this study sheds light on the validation of numerical studies of vascular flow against experimental studies and on which flow model best fits the experimental data.