Abstract
The effect of blood flow on the dynamic instability of a viscoelastic micro blood vessels (MBVs) is investigated in this study. The blood flow includes red blood cells (RBCs), blood flow profile, related modification factors and hematocrit are considered. The supporting tissues around the blood vessel are assumed as the viscous fluid. The governing equation of MBVs are obtained by the extended Hamilton’s principle based on the modified couple stress theory (MCST). The extended Galerkin approach is used in order to transform the resulting equations into general eigenvalue equations. The validity and accuracy of the present numerical scheme is confirmed by comparing the results with those obtained in literature and excellent agreement is achieved. The results show that the critical dynamic blood flow velocity, which leads to instability, is dependent on the constitutional material gradient scale, structural damping of blood vessel, viscous fluid and blood flow characteristics. Moreover, it is revealed that the MCST has a significant influence on the critical dynamic blood flow velocity of vessels. Also, it is demonstrated that by increasing the hematocrit and the mass ratio of blood flow, the critical dynamic blood flow velocity increases, while it decreases as the RBCs diameter, vessel’s diameter and internal pressure increase.