两维和三维蛇形通道中的粘弹性流量的比较
Himani Garg1, Christer Fureby1
1Department of Energy Sciences, <a href="https://ror.org/012a77v79">Lund University</a>, P. O. Box 118, SE-22100 Lund, Sweden.
Physical review. E
|June 22, 2024
概括
在蛇形通道中对粘弹性流体流量的数值模拟显示出纯弹性不稳定性. 二维模型准确地捕捉了这种弹性流的关键特征,这是由流体几何而不是二次流动驱动的.
科学领域:
- 流体动力学 流体动力学
- 聚合物物理 聚合物物理
- 类风病学 类风病学 类风病学
背景情况:
- 稀释聚合物溶液表现出复杂的质性质,对于工业应用至关重要.
- 了解复杂几何体中的粘弹性流体动力学,需要进行彻底的数值分析.
- 粘弹性流体中的纯弹性不稳定性是一种具有重大科学意义的现象.
研究的目的:
- 在2D和3D蛇形通道中数量研究纯弹性不稳定性.
- 在可忽略不计的惯性下分析各种聚合物放松时间的流动动力学.
- 将二维和三维模拟结果与实验数据进行比较.
主要方法:
- 使用Oldroyd-B模型对粘弹性流体流量的数值模拟.
- 对二维和三维蛇形通道几何学的研究.
- 分析空间流动模式和时间流动统计.
主要成果:
- 灵活的聚合物解决方案的2D/3D模拟和实验结果之间具有很强的质量一致性.
- 弹性流的特点是非均的,非高斯的和异型的特征.
- 由流线曲率驱动的不稳定性,2D模拟有效地复制了3D实验观测.
结论:
- 二维数值模拟足以从质上捕捉弹性流特征.
- 蛇形通道中的流线曲率是弹性不稳定的主要驱动因素.
- 与其他方案相比,稀释弹性流中的兴奋波动尺度较窄.
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