用于人体降主动脉的各向异性分数阶黏弹性本构模型。

Anisotropic fractional viscoelastic constitutive models for human descending thoracic aortas.

机构信息

Department of Mechanical Engineering, McGill University, 817 Sherbrooke Street West, Montreal, H3A 0C3, Canada; Department of Biomedical Engineering, McGill University, 817 Sherbrooke Street West, Montreal, H3A 0C3, Canada.

Department of Mechanical Engineering, McGill University, 817 Sherbrooke Street West, Montreal, H3A 0C3, Canada.

出版信息

J Mech Behav Biomed Mater. 2019 Nov;99:186-197. doi: 10.1016/j.jmbbm.2019.07.010. Epub 2019 Jul 19.

DOI:10.1016/j.jmbbm.2019.07.010

PMID:31362261

Abstract

The generalized fractional Maxwell model, formulated for hyperelastic material within the framework of the nonlinear viscoelasticity with internal variables, is applied to identify viscoelastic constitutive equations from layer-specific experimental data obtained by uniaxial harmonic loading of ex-vivo human descending thoracic aortas. The constitutive parameters are identified by using a genetic algorithm for the optimal fitting of the experimental data. The accuracy of the fitted fractional model is compared to the fitted integer order model with the same number of Maxwell elements. The formulation of an original strain energy density function for anisotropic nonlinear viscoelasticity is introduced and constitutive parameters are obtained from the experiments.

摘要

广义分数阶 Maxwell 模型是在具有内变量的非线性粘弹性框架内为超弹性材料构建的，用于从通过离体人降主动脉单轴谐波加载获得的特定于层的实验数据中识别粘弹性本构方程。本构参数通过遗传算法进行识别，以实现实验数据的最佳拟合。将拟合的分数阶模型与具有相同数量 Maxwell 元件的拟合整数阶模型进行比较，以评估拟合分数阶模型的准确性。介绍了各向异性非线性粘弹性的原始应变能密度函数的公式，并从实验中获得本构参数。