关于使用有限元素方法对墙壁剪切应力的数值评估
Jana Brunátová1,2, Jørgen S Dokken3, Kristian Valen-Sendstad4
1Mathematical Institute, Charles University, Prague, Czechia.
International journal for numerical methods in biomedical engineering
|September 12, 2025
概括
精确计算壁切应力 (WSS) 对心血管研究至关重要. 本研究比较了WSS的有限元素方法,引入了边界流量方法,并强调了元素选择对患者特异性动脉瘤模型可靠结果的重要性.
科学领域:
- 计算流体动力学 计算流体动力学
- 生物医学工程 生物医学工程
- 心血管研究的心血管研究.
背景情况:
- 壁切应力 (WSS) 是心血管研究中的一个关键的血液动力学参数.
- 使用有限元素方法 (FEM) 精确的数值计算WSS提出了挑战.
- 现有的WSS评估方法可能对离散选择和网格质量敏感.
研究的目的:
- 为了比较不同有限元离散的WSS结果.
- 量化连续和不连续应力计算之间的差异.
- 为WSS计算引入和评估一个修改的变化一致的边界流量方法.
主要方法:
- 比较P1/P1稳定和泰勒-胡德P2/P1混合有限元素的速度和压力.
- 使用新型边界流量方法和投射到P1,DG-1和DG-0空间的WSS计算.
- 适用于比较2D冲刺和3D波西耶流动,以及患者特定的动脉瘤模型.
主要成果:
- 边界流和P1投影方法对P1/P1元素产生同等结果.
- P2/P1元素在Poiseuille流中与边界流的收速度更快,但对复杂几何形状中的压力误差敏感.
- 在动脉瘤WSS和低剪切面积 (LSA) 计算中,P2/P1元件显示出高于网状网状尺寸的强度.
结论:
- 选择有限元空间显著影响WSS的准确性,特别是在复杂的几何形状,如动脉瘤.
- 拟议的边界流量方法提供了优势,但需要仔细考虑元素选择和网格精细化.
- 仔细选择有限元空间对于心血管应用中可靠的WSS计算至关重要.
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