The effect of boundary slip on transient non-Newtonian blood flows under pulsatile pressure

In this work, we investigate the influence of boundary slip for two pulsatile flow problems. The first problem is considered with the transient axially symmetric flows of fluids through vessels taking into account the Fahraeus-Lindqvist effect. The second problem is on general three-dimensional blood flows in the human right coronary artery. Both analytical and numerical results are presented to show the flow phenomena and the influence of the slip parameter on the flow behaviour

The effect of boundary slip on the transient pulsatile flow of a modified second-grade fluid

We investigate the effect of boundary slip on the transient pulsatile fluid flow through a vessel with body acceleration. The Fahraeus-Lindqvist effect, expressing the fluid behavior near the wall by the Newtonian fluid while in the core by a non-Newtonian fluid, is also taken into account. To describe the non-Newtonian behavior, we use the modified second-grade fluid model in which the viscosity and the normal stresses are represented in terms of the shear rate. The complete set of equations are then established and formulated in a dimensionless form. For a special case of the material parameter, we derive an analytical solution for the problem, while for the general case, we solve the problem numerically. Our subsequent analytical and numerical results show that the slip parameter has a very significant influence on the velocity profile and also on the convergence rate of the numerical solutions

Oscillating pressure-driven slip flow and heat transfer through an elliptical microchannel

© 2019, The Author(s). This paper studies the transient slip flow and heat transfer of a fluid driven by the oscillatory pressure gradient in a microchannel of elliptic cross section. The boundary value problem for the thermal-slip flow is formulated based on the assumption that the fluid flow is fully developed. The semi-analytical solutions of velocity and temperature fields are then determined by the Ritz method. These solutions include some existing known examples as special cases. The effects of the slip length and the ratio of minor to major axis of the elliptic cross section on the velocity and temperature distribution in the microchannel are investigated