The Effects of Blood Flow on Blood Vessel Buckling Embedded in Surrounding Soft Tissues

Abstract

When blood flows in vessel curved portion, the presence of curvature generates a centrifugal force that acts in the same manner as a compressive load. Therefore, blood flow velocity has an important effect on the stability of vessels. In this study, the blood vessel is simulated as a flexible beam conveying fluid base on Euler–Bernoulli beam theory, and various boundary conditions are represented for the modeled vessels. Then, analytical and numerical methods are deployed to extract desired parameters. The effects of blood flow, hematocrit and stiffness of surrounding tissues on the buckling critical pressure are investigated. The results show that the mentioned parameters have considerable effects on blood vessels stability. Several numerical findings illustrate a reduction in critical buckling pressure with increasing hematocrit and blood flow velocity. In addition, the size of red blood cell has a significant effect on critical buckling pressure in low hematocrits. As increasing red blood cell diameter decreases critical buckling pressure. Furthermore, because of blood viscosity, the non-uniformity effects of the blood flow on blood vessels stability are investigated by considering a modification factor. These results improve our understanding of blood vessels instability.