虚拟场方法在超弹性材料的膨胀膨胀测试中的实验不均性方面有多强大?
Paulien Vandemaele1, Lauranne Maes1, Heleen Fehervary2
1Biomechanics Section, Department of Mechanical Engineering, KU Leuven, Leuven, Belgium.
Journal of the mechanical behavior of biomedical materials
|March 28, 2025
概括
虚拟场方法准确地识别软组织中的材料参数,即使厚度不均. 考虑到特定区域的厚度可以提高准确性,强调该方法在机械表征方面的稳定性.
科学领域:
- 生物力学 生物力学
- 材料科学 材料科学 材料科学
- 计算力学 计算力学 计算力学
背景情况:
- 生物软组织的机械表征是复杂的,因为固有的不均性.
- 使用虚拟场方法 (VFM) 的构成模型校准利用区域特定参数的全场数据.
- 实际的VFM应用通常通过使用平均厚度和推导均参数来简化,这可能会影响准确性.
研究的目的:
- 调查简化假设 (平均厚度,均参数) 对VFM预测的材料参数的影响.
- 在不同的条件下评估VFM准确性:均,不均的厚度和不均的材料特性.
- 评估VFM对降低数据分辨率的稳定性.
主要方法:
- 从有限元模型模拟的膨胀实验中创建合成数据集.
- 使用虚拟场方法识别参数,使用不同级别的厚度和材料属性数据.
- 将VFM衍生的参数和应激反应与地面真相值进行比较.
主要成果:
- 高精度 (0.15%的误差) 在同质样本中实现,即使有部分变形数据.
- 不统一的厚度样本给出了使用平均厚度的参数有4%的误差,但当包括特定区域的厚度时,误差为<1%.
- 不同质的材料特性导致了同质化的应激反应,掩盖了基本真理的极端;VFM显示了0.6%的增量误差. 通过降低分辨率.
结论:
- 考虑到特定区域的厚度,可以显著提高软组织中VFM参数识别的准确性.
- 虚拟场方法证明了对样品厚度和材料不均性的变化具有稳定性.
- 结果表明VFM在不同的实验设置和组织类型中具有适用性和可靠性.
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