在Giesekus模型中考虑一个非常数的异性变性参数
Fatemeh Karami1, Pavlos S Stephanou2
1Department of Mechanical Engineering, Lorestan University, Khorramabad 68151-44316, Iran.
Polymers
|September 27, 2025
概括
吉塞库斯模型被修改为允许一个可变的异构性参数,改进了剪切流中的第二个正常应力系数的预测. 这种学模型的修改更好地与实验数据保持一致,特别是在启动流程中.
科学领域:
- 类风病学 类风病学 类风病学
- 聚合物物理 聚合物物理
- 流体力学 流体力学 流体力学
背景情况:
- 吉塞库斯模型 (Giesekus model) 是一种在风湿学中广泛使用的构成模型.
- 在Giesekus模型中,异构性参数传统上被视为常数.
- 最近的发现表明,异性异性参数可能有所不同.
研究的目的:
- 在Giesekus模型中研究可变的异构性系数的含义.
- 开发一个修改过的Giesekus模型,具有非常数的异构性参数.
- 将修改模型的预测与实验数据进行比较.
主要方法:
- 修改Giesekus构成方程,以纳入一个可变的异构性参数.
- 分析模型对简单剪流中的第二个正常应力系数的预测.
- 与文献中现有的实验数据进行比较.
主要成果:
- 经过修改的Giesekus模型具有可变的异构性系数,在预测第二个正常应力系数方面显示出显著的差异.
- 一个关键的发现是第二个正常应力系数的线性粘弹性外的转移到更高的值.
- 这种转变在初始简单剪流场景中尤其明显.
结论:
- 在Giesekus模型中允许异构性参数变化,从而可以更好地预测质行为.
- 修改后的模型提供了与实验观测更一致的结果,特别是对于短暂的剪切流.
- 这项研究提出了一种新的风学模型,在聚合物加工和流体动力学方面具有潜在的应用.
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