脂肪组织材料本构模型参数力学响应灵敏度分析

Analysisof Constitutive Model Parameters of Adipose Tissue Materials on Mechanical Response Sensitivity

【目的】确定脂肪组织材料各材料本构的参数灵敏度,以便合理简化参数反求变量,提高材料对标效率。【方法】采用对4种常用的脂肪组织材料本构模型进行无约束压缩试验,研究各材料参数对力学响应的影响情况。【结果】线性黏弹性材料本构中短效剪切模量与衰减常数对接触力影响显著,Mooney-Rivlin超弹性本构中材料常数对接触力值影响较大,Ogden超弹性本构模型中Og⁃den系数对接触力值影响最显著,软组织材料本构中材料常数对接触力影响显著。【结论】为脂肪组织材料力学性能研究、参数反求及材料对标工作的合理简化提供了参考,极大地提高了计算效率。

[Purposes]The parameter sensitivity of each material constitutive of adipose material was determined in order to simplify the inverse parameter variables reasonably and improve the efficiency of material calibration.[Methods]Unconstrained compression tests were carried out on four commonly used material constitutive models of adipose tissue,and the parameters of each material constitutive model were and analyzed to study the influence of each material parameter on the mechanical response of each material constitutive model.[Findings]The results show that the short-time shear modulus and decay constant have significant effects on the maximum contact force in the linear viscoelastic material.In the Mooney-Rivlin hyperelastic constitutive,the material constant has a greater influence on the maximum contact force,the Ogden coefficient has the most significant effect on the maximum contact force in the Ogden hyperelastic constitutive model.The influence of material constants on the maximum contact force is significant for soft issue constitutive model.[Conclusions]It provides a reference for the rational simplification of adipose tissue material mechanical properties research and parameter inversion work,and greatly improves the calculation efficiency.