控制复杂流体的粘性指纹不稳定性
Alban Pouplard1, Peichun Amy Tsai2
1Department of Mechanical Engineering, University of Alberta, Edmonton, AB, T6G 2G8, Canada.
Scientific reports
|January 28, 2024
概括
控制多孔介质中的粘性指纹对于增强石油回收等技术至关重要. 这项研究表明,渐变细胞如何抑制复杂流体中的这些不稳定性,从而实现稳定的流体位移.
科学领域:
- 流体动力学 流体动力学
- 孔隙介质物理学的物理
- 类风病学 类风病学 类风病学
背景情况:
- 粘性指纹,以波纹或指纹图案为特征,发生在低粘度流体在多孔介质中取代高粘度流体时.
- 这些不稳定性导致扫除效率不完全,对增强的石油回收,染色学和地下水整治等技术产生负面影响.
- 由于流体之间固有的移动性对比,控制这些指纹模式具有挑战性,这通常决定了接口稳定性.
研究的目的:
- 调查复杂流体中抑制或控制粘性指纹不稳定的方法.
- 探索使用带有线性变化的间隙厚度的辐射缩细胞来管理流体-流体接口稳定性.
- 开发一个理论框架,用于预测和控制微流体和多孔介质应用中的这些模式.
主要方法:
- 复杂粘性液体 (聚烯胺溶液) 与气体在线性变化的间隙厚度的半径收细胞中的实验性移位.
- 系统变化气体流速 (Q) 和细胞间隙厚度梯度 ([公式:见文本]) 来观察接口行为.
- 使用简化的线性稳定性分析来预测接口稳定性标准的理论分析.
主要成果:
- 对于复杂的流体,在低流速 (Q) 和更的梯度 ([公式:见文本]) 的细胞中,可以实现稳定,均的接口.
- 在高流速 (Q) 和较小梯度的细胞中观察到不稳定的指纹模式 ().
- 理论预测与实验数据有很好的一致性,提供了定量稳定性标准.
结论:
- 一个带有线性变化的间隙厚度的辐射渐变细胞可以有效地抑制复杂流体中的粘性指纹不稳定性.
- 该研究提供了一种定量策略,通过调整流量和细胞几何学来控制微流体和多孔介质中的流体流体模式和位移.
- 这项研究为优化依赖于在多孔环境中稳定流体位移的技术提供了宝贵的见解.
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