Hemodynamic Numerical Computation And Analysis Of Carotid Artery

In2007, the statistics from China’s Ministry of Health shows that vascular disease has been one of the main threaten of human health. Now more and more people have devoted themselves to the study of vascular hemodynamics. In clinical, it had been proved that the occurred possibility of vascular disease in crotch or big flexibility is higher than other position. For carotid artery model, carotid internal artery and carotid external artery begin at the carotid common artery, due to the special physiological geometry structure, carotid sinus is the part which is a little than others, and which is located in under of internal carotid artery, which has high possibility of vascular disease.With the continually development of CFD technology, the technology of computer fluid dynamic is more and more mature, the combination of CFD technology and medical imaging technology, which also is called the combination of engineering and medicine, is the main method of studying hemodynamic field. For the numerical computation of blood, in the process of simulation, what should be considered is the property of density of liquid, dynamic viscosity, temperature, gravity, Newtonian fluid or non Newtonian fluid, and so on. In this experiment, blood is non Newtonian fluid. In CFX module of the finite element software ANSYS, the process of numerical simulation is to solve Navier-Stokes equations, which records the motion tracks of all particles, and abides by three laws of motion, law of conservation of mass, law of conservation of momentum, and law of conservation of energy.In this thesis, by simulating the no plaque carotid artery model and small plaque model, analyzing the wall shear on the blood wall of carotid artery model without plaque in a cardiac cycle, and then determining the location of plaque where to be built, observing the velocity field on the plane of carotid artery sinus, and contrasting the difference of eddy current at systole and diastole in a cardiac cycle, in order to ensure when the blood flow starts to be steady and the emerging and disappeared moment of eddy current, meanwhile, this thesis then compares the blood flux between the two models, and blood resistance distribution with time. Finally, the experiment indicates that the wall shear almost is lowest on the sinus of no plaque model, and from systole on, the eddy current begins, the eddy current radius gradually begins to be larger, and ends up during diastole, this moment is nearly0.4second, when the eddy current almost disappears. Between the two models, the blood flux decease in internal carotid artery of small plaque model than no plaque model’s, and the blood resistance is higher than no plaque model in diastole, but in systole, the resistance of two models is not so obviously.