Numerical Simulation Of Blood And Thrombus Flow In Different Blood Vessels

Thrombosis is a global disease.Thrombosis can appear in blood vessels with large changes in hemodynamics.It is of great significance to study the thrombus formation and movement,and it can guide the clinical prevention of thrombosis risk.In this study,the computational fluid dynamics software FLUENT was used,and physical models of different blood vessels were established.Combined with the elements of thrombosis,the location of possible thrombosis in different blood vessels was analyzed.In vein,the effects of different valve lengths and sinus sizes on hemodynamics were investigated.The study found that the blood flow in sinus has a low flow rate.As the length of the valve and the volume of the sinus increased,the velocity and the wall shear stress decreased in the sinus,which would increase the risk of thrombosis.In vein with a diameter of 5 mm,when the distance between adjacent venous valves was 2 mm and the angle was 90°,the spiral flow of blood was more obvious,stasis of blood stream phenomenon was not obvious.In curved vessels,the effects of vessel diameter,bending angle and radius of curvature on hemodynamics were studied.The results showed that the inner side of the curved blood vessel was a low-velocity area,so this area is prone to thrombosis.The reduction of the bending angle and radius of curvature caused the low speed zone to affect a larger range.The larger vascular diameter,the lower the blood flow velocity.In bifurcated blood vessels,the wall shear stress and blood flow velocity outside the bifurcation were low,so thrombosis was likely to occur in this region.The particle residence time increased with bigger bifurcation angle.The larger the diameter of the branch blood vessel,the greater the influence range of the low-velocity area,and the lower the shear stress.When there was plaque in the aortic arch,the shear rate of the occlusion site increased with the higher vascular occlusion rate,and it was likely to activate platelets to form thrombosis.The velocity and shear force within the aneurysm reduced with larger aneurysm in the aortic arch.The computational results showed that enlargement of the aortic arch aneurysm and higher rate of blockage can lead to thrombosis.The movement of thrombus of different sizes in blood vessels was studied.The degree of thrombus damage to the wall of the blood vessel increased with bigger thrombus.The shear stress of the thrombus on the aneurysm decreased as the diameter of the aneurysm increased.In blood vessels with different bifurcation angles,thrombus had different trajectories.When the bifurcation angle increased or the blood vessel diameter decreased,the direction of thrombus flow was unlikely to change significantly.