Effects of Inclination of Micro-capillary on Blood-Viscosity of Diseased Blood in Presence of Metallic Ball

Abstract

Dynamic changes in rheology of blood within microvasculature structures can be used for diagnosing chronic non-communicable disease at earlier stages. Behavior of blood in microvascular structures (capillaries) is mysterious. In case of capillaries present in brain, such dynamic continuum induces hindrance to oxygen diffusion through circumvented nerve fibers at the junction of blood-brain barriers. It causes temporary regional hypoxia. Therefore, understanding the rheology of blood in micro-confined capillaries may evolve as a tool for early prediction of hypoxia. Viscosity of blood in micro-capillaries can be measured by principle of falling ball viscometer. But this technique produces inconsistent result for non-Newtonian fluid. In this paper, we have presented an investigation on dynamic behavior of blood rheology within micro-capillaries inclined at different degrees of inclinations. Experimental results are complemented with detailed numerical simulations. Experimental observations reveal significant variation of rheological parameters of blood in micro-capillaries. Inter-gender variations confirm the contribution of hematocrit in blood for this variation. The rheological parameters of blood with diseased condition are found to vary with the different degrees of inclination of the micro-capillary. Effect of rolling ball on the red blood cells (RBCs) during interaction in the capillary of the viscometer is found to induce deformative stress on membrane of RBC. It is also confirmed by the continuous sustainability of the higher magnitude strain rate near the wall (between boundaries of ball and wall). Inclined angle of capillary tube was also found as a parameter for defining rheology of blood in micro-capillary.