Linear and Nonlinear Viscoelastic Arterial Wall Models: Application on Animals.
This work deals with the viscoelasticity of the arterial wall and its influence on the pulse waves. We describe the viscoelasticity by a nonlinear Kelvin-Voigt model in which the coefficients are fitted using experimental time series of pressure and radius measured on a sheep's arterial network. We obtained a good agreement between the results of the nonlinear Kelvin-Voigt model and the experimental measurements. We found that the viscoelastic relaxation time-defined by the ratio between the viscoelastic coefficient and the Young's modulus-is nearly constant throughout the network. Therefore, as it is well known that smaller arteries are stiffer, the viscoelastic coefficient rises when approaching the peripheral sites to compensate the rise of the Young's modulus, resulting in a higher damping effect. We incorporated the fitted viscoelastic coefficients in a nonlinear 1D fluid model to compute the pulse waves in the network. The damping effect of viscoelasticity on the high-frequency waves is clear especially at the peripheral sites.
CNRS UMR 7190, Institut Jean le Rond ?'Alembert, UPMC Univ Paris 06, Sorbonne Universités, Paris F-75005, France.
Arthur R
AR
Ghigo
CNRS UMR 7190, Institut Jean le Rond ?'Alembert, UPMC Univ Paris 06, Sorbonne Universités, Paris F-75005, France.
Xiao-Fei
XF
Wang
Faculty of Engineering and Natural and Exact Sciences, Favaloro University, Buenos Aires C1078AAI, Argentina.
Ricardo
R
Armentano
CNRS UMR 7190, Institut Jean le Rond ?'Alembert, UPMC Univ Paris 06, Sorbonne Universités, Paris F-75005, France.
Jose-Maria
JM
Fullana
CNRS UMR 7190, Institut Jean le Rond ?'Alembert, UPMC Univ Paris 06, Sorbonne Universités, Paris F-75005, France.
Pierre-Yves
PY
Lagrée
D000818:Animals; D001158:Arteries / Q000033:anatomy & histology / Q000502:physiology*; D001783:Blood Flow Velocity / Q000502:physiology; D001794:Blood Pressure / Q000502:physiology; D019245:Compressive Strength / Q000502:physiology; D003198:Computer Simulation; D055119:Elastic Modulus / Q000502:physiology*; D066298:In Vitro Techniques; D016014:Linear Models; D008955:Models, Cardiovascular; D017711:Nonlinear Dynamics; D033081:Shear Strength / Q000502:physiology; D012756:Sheep; D013314:Stress, Mechanical; D013718:Tensile Strength / Q000502:physiology; D014783:Viscosity