TY - EJOU AU - Liu, Xiang AU - Sun, Liangbo AU - Wang, Mingzhen AU - Li, Bin AU - Liu, Lisheng TI - Modeling and Simulation of Valve Cycle in Vein Using an Immersed Finite Element Method T2 - Computer Modeling in Engineering \& Sciences PY - 2020 VL - 123 IS - 1 SN - 1526-1506 AB - A vein model was established to simulate the periodic characteristics of blood flow and valve deformation in blood-induced valve cycles. Using an immersed finite element method which was modified by a ghost fluid technique, the interaction between the vein and blood was simulated. With an independent solid solver, the contact force between vein tissues was calculated using an adhesive contact method. A benchmark simulation of the normal valve cycle validated the proposed model for a healthy vein. Both the opening orifice and blood flow rate agreed with those in the physiology. Low blood shear stress and maximum leaflet stress were also seen in the base region of the valve. On the basis of the healthy model, a diseased vein model was subsequently built to explore the sinus lesions, namely, fibrosis and atrophy which are assumed stiffening and softening of the sinus. Our results showed the opening orifice of the diseased vein was inversely proportional to the corresponding modulus of the sinus. A drop in the transvalvular pressure gradient resulted from the sinus lesion. Compared to the fibrosis, the atrophy of the sinus apparently improved the vein deformability but simultaneously accelerated the deterioration of venous disease and increased the risk of potential fracture. These results provide understandings of the normal/abnormal valve cycle in vein, and can be also helpful for the prosthesis design. KW - Numerical simulation KW - fluid-structure interaction KW - immersed finite element method KW - adhesive contact method KW - bio-mechanics KW - venous valve DO - 10.32604/cmes.2020.08716