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... to save computational resources. Triangular elements were used to mesh faces. T-Grid Scheme was used to mesh the artery; in this scheme tetrahedral volume elements are constructed due to which mesh becomes aligned with curved wall of artery [14]. Meshing of healthy model is shown in Fig. 3. Meshing of three other models with plaques is shown in Fig. 4. Mesh size was nearly equal in all cases. ...
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... The lack of any other type of solution, we chose numerical method established on finite element discretization. This element discretization consists of shape functions that possesses 9 degrees of freedom for velocity and 3 local degrees of freedom for pressure approximation 36,37 . The direct type solver is iterated after linearizing the existing nonlinear algebraic system. ...
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The mortality rates due to cardiovascular diseases are on a rise globally. One of the major cardiovascular diseases is stroke which occurs due to atherosclerotic plaques build-up in the carotid artery. The common carotid artery (CCA) bifurcates into the internal carotid artery (ICA) and external carotid artery (ECA). Sinus present at ICA is an ellipsoidal-shaped dilated region acting as a pressure receptor and blood flow regulator. Dimensions of the sinus vary from person to person, affecting the hemodynamics of the carotid artery. The current numerical study manifests a 3D flow analysis by varying the sinus length to investigate its local and global effects on the hemodynamics of the carotid artery using various biomechanical risk analysis parameters of atherosclerosis. User-defined function (UDF) dictates the pulsatile flow velocity profile imposed at the inlet. Near the outer wall (OW) of the sinus, the blood flow velocities are lower and recirculation zones are more. Though the recirculation zones for shorter sinus will be close to the inner wall (IW), interestingly, with an increase in the sinus length, the recirculation zones shift toward the OW with higher strength. These significantly decrease the x-wall shear stress (x-WSS) and time-averaged wall shear stress (TAWSS) values on the OW of the longer sinus. The other risk analysis parameters, like oscillatory shear index (OSI) and relative residence time (RRT), support the described consequences. These results reveal that sinus of increased length is more prone to developing atherosclerotic plaque.
