Radiation and MHD effects on an oscillatory flow of a Jeffrey fluid in a circular tube

SummaryPlatelet thrombi in suspensions stirred in an aggregometer or subjected to shear flow in a Couette viscometer or circular tube can only form as a result of collisions between the cells. In whole blood, the presence of the red cells results in pronounced lateral displacements of the paths of the platelets through the vessel, which in turn increases the frequency of collisions between platelets and also makes possible platelet-wall interactions. In addition, blood cells in a suspension undergoing shear flow are subjected to fluid stresses which can result in their deformation. Such stresses may locally attain high values in the arterial circulation at bifurcations, sharp bends and stenoses where the flow is disturbed. Since platelet thrombi have been found downstream of sites of such geometry, the effects of high and variable shear stress on the platelet release reaction and aggregation were investigated. Washed platelets containing C14-serotonin in Tyrodes-albumin solution were subjected to oscillatory flow at 37° C and provided the time average wall velocity gradient was above 2,000 sec-1, the thrombin-induced release of serotonin was appreciably greater than in the corresponding controls incubated at rest. No measurable serotonin was released as a result of flow alone. This synergistic effect of oscillatory shear flow was also noted in the presence of inhibitors of the release reaction.

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Influence of Varying Temperature and Concentration on MHD Peristaltic Transport for Jeffrey Fluid with Variable Viscosity through Porous Channel

Journal of Al-Qadisiyah for Computer Science and Mathematics ◽

10.29304/jqcm.2019.11.3.586 ◽

2019 ◽

Vol 11 (3) ◽

Author(s):

Ahmed A . Hussein Al-Aridhee ◽

Dheia G. Salih Al-Khafajy

Keyword(s):

Schmidt Number ◽

Magnetic Parameter ◽

Circular Tube ◽

Variable Viscosity ◽

Darcy Number ◽

Jeffrey Fluid ◽

Physical Parameters ◽

Peristaltic Motion ◽

Analytical Formulas ◽

Numerical Formula

The present paper deals with the peristaltic motion of Jeffrey fluid with varying temperature and concentration through a porous medium in a coaxial uniform circular tube. The fluid is assumed to be non-Newtonian, namely Jeffrey fluid. The inner tube is uniform, while the outer flexible tube has a sinusoidal wave traveling down its wall. The analytical formulas of the velocity and temperature have been obtained in terms of the Bessel function of first and second kinds. The numerical formula of the axial velocity, temperature and concentration are obtained as functions of the physical parameters of the problem (Darcy number, magnetic parameter, thermal Grashof number, Reynolds number, Prandtl number, and Schmidt number) with other physical parameters are obtained. The Influence of physical parameters of the problem on this formula are discussed numerically and illustrated graphically through a set of figures.

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