在剪切稀释和弹性可塑性流体中使用流体算法的几何体积的单泡上升
Ahmad Fakhari1, Célio Fernandes2,3
1Department of Biophysics, University of Texas Southwestern Medical Center, 6001 Forest Park Rd, Dallas, TX 75390, USA.
Polymers
|August 26, 2023
概括
这项研究引入了一种新的计算方法,用于模拟复杂流体中的气泡. 该算法准确地模拟了牛顿式,粘弹性和弹性塑性流体中的泡行为,从而实现了各种工业应用.
科学领域:
- 多相流动动力学 多相流动力学
- 计算流体动力学的流体动力学.
- 非牛顿流体力学的流体力学.
背景情况:
- 空气泡运动对于传热和材料质量至关重要.
- 非牛顿流体的特性,如粘度,受到气泡的显著影响.
- 精确模拟复杂流体中的气泡动力学是一项挑战.
研究的目的:
- 开发和验证一种用于多相粘弹性流体流动的新型接口捕获方法.
- 准确模拟浮力驱动的气泡在不同复杂度的流体中的上升.
- 为涉及复杂流体中的泡动态应用提供强大的计算工具.
主要方法:
- 开发了一种流体 (isoAdvector) 的几何体积方法.
- 使用重建距离函数 (RDF) 进行界面曲率.
- 为了提高准确性,采用了一种逐段线性接口构造 (PLIC) 方案.
- 验证了多相粘弹性PLIC-RDF isoAdvector (MVP-RIA) 算法,使用牛顿式,粘弹性和弹性粘弹性流体的模拟.
主要成果:
- MVP-RIA算法准确地预测了牛顿流体中的气泡形状和速度,与实验数据相匹配.
- 在粘弹性流体中的模拟显示,由于正常应力效应,泡形状转变为前置/滴水形状.
- 在elastoviscoplastic流体中,气泡变形仅限于小气泡,在更大的体积中演变为具有多个尾巴的长形状.
- 与传统的代数流体体积 (VOF) 方法相比,在较粗的网格上获得了准确的结果.
结论:
- 开发的MVP-RIA算法为模拟多相粘弹性流体流动提供了强大而准确的方法.
- 该研究表明,该算法能够捕获各种非牛顿流体中复杂的泡变形和形状转换.
- 这一进步为工业应用中改进的模拟铺平了道路,例如泡柱,聚合物加工和3D打印.
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