The FSI-module of Elmer can be used to simulate the pulsatile blood flow in elastic blood vessels.
In addition to the blood transporting function, the larger arteries of human body perform also a cushioning function that transforms the pulsatile flow generated by the left ventricle into a steady flow at the periferial arteries. Arterial elasticity, compliance, is principal determinant of arterial pressure. About a half of the volume of physilogical pulse of blood is transported straight to the perifery during the systolic phase and the rest of the blood is accumulated in the elastic arteries. During the diastolic phase the accumulated blood is moved forward into the circulation system.
The beating heart creates also pressure waves which propagate through aorta and reflects back from periferial circulation and also from all kinds of mechanical and geometrical discontinues like stenosis and bifurcations.
Three picture below shows solutions on pressure pulse propagation in human large arteries, diameter of 20 mm. Wall density is 1100 kg/m3, Young's modulus 4.5E5 Pa, blood density 1050 kg/m3 and blood viscosity 3.5E-3 Pa s. During 5 ms a pressure pulse of 1333 Pa (10 mmHg) is sent in at the inlet of the conduit.
Note. The displacements are exaggerated. Color scale represents the pressure.
Elastic carotid artery
100 ms pulse, max pressure 8000 Pa.No magnification in the animation.