The study investigated the effect of the angular position of the head on the blood flow in the jugular vein of giraffes. The vein considered is elastic and collapsible such that its cross-sectional area is not uniform. Transmural pressure causes the blood to move along the vein. Mathematical equations describing the flow were developed, and the vein was considered to be inclined at an angle φ to the horizontal. A finite-difference scheme was used to solve the equations of motion for the flow. The results are presented via relevant tables and plots. Our findings show that a change in the position of the head causes variation in the external pressure, which in turn causes variation in the cross-sectional area of the vein. Moreover, a drop (or increase) in the inertial pressure of the blood may cause the vein to collapse (or distend), which again triggers a change in the pressure.
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