[论文解读] Applications of elastic instability and elastic turbulence: Review, limitations, and future directions

C. Sasmal|arXiv (Cornell University)|Jan 6, 2023

Rheology and Fluid Dynamics Studies被引用 5

一句话总结

本文综述了弹性失稳（EI）和弹性湍流（ET）在微流体混合、微尺度传热及化学驱油（EOR）中的应用，强调其在增强传质过程方面的潜力。文章指出了当前研究中的关键局限性，并呼吁未来开展关于电驱动ET、孔隙尺度动力学及实际应用的研究。

ABSTRACT

Viscoelastic fluids are a subclass of complex fluids used in widespread applications ranging from biological to large-scale industrial settings. These fluids are often associated with various complex flow phenomena due to the presence of non-linear elastic stresses, originating due to the stretching and relaxation phenomena of microstructure (such as polymer molecules in the case of a viscoelastic polymer solution) in a deformed flow field. One such phenomenon is elastic instability (EI) which emerges due to the interaction between elastic stresses and streamline curvature present in a flow system at small values of the Renolds number (ratio of the inertial to that of the viscous forces) when the Weissenberg number (ratio of the microstructure relaxation time to that of the rate of flow deformation) exceeds a critical value. On further increasing this Weissenberg number to higher values, the unstable flow field caused due to this elastic instability transits to a more chaotic and turbulent-like flow structure called elastic turbulence (ET). Over the last two decades or so, an extensive investigation has been performed on this particular topic in the complex fluids research community. Some excellent articles recently present this ET phenomenon's development, understanding, and progress in the literature. This article focuses on the application perspectives of this phenomenon. In particular, this article aims to provide a comprehensive review of the investigations conducted so far in the literature to demonstrate the potential of these EI and ET phenomena in three main application areas, namely, microfluidic mixing, microscale heat transfer, and chemically enhanced oil recovery (EOR) process. Additionally, a detailed discussion of the limitations and future directions of these EI and ET phenomena from an application point of view is also presented in this article.

研究动机与目标

• 全面综述弹性失稳（EI）和弹性湍流（ET）在微流体系统、传热及提高原油采收率（EOR）中应用的潜力。
• 识别当前实验与模拟研究中与EI和ET相关的关键局限性，特别是实际适用性与系统复杂性方面的问题。
• 强调在涉及聚合物表面活性剂和非牛顿原油等复杂流体体系中，ET的孔隙尺度研究严重缺乏。
• 倡导未来开展关于电驱动ET的研究，因其在无活动部件的微流体器件中具有优势。
• 推动基于实际应用的实验研究，以验证EI和ET在微热沉和芯片上实验室反应器等实际工程系统中的可行性。

提出的方法

• 对微流体混合、微尺度传热及EOR三个应用领域中关于EI和ET的实验与数值研究进行系统性文献综述。
• 分析韦森堡数（Wi = λγ̇）作为控制EI起始与向ET过渡的关键无量纲参数。
• 利用计算流体动力学（CFD）与直接数值模拟（DNS）评估流动动力学，以模拟粘弹应力发展与失稳起始。
• 采用粒子图像测速（PIV）与斜射成像技术实验可视化ET引起的混沌流动结构。
• 比较压力驱动与电驱动流动系统，评估在低雷诺数微流控平台中ET生成的可行性。
• 在孔隙尺度模拟中引入驱替流体（如聚合物溶液）与被驱替流体（如剪切稀化原油）的流变模型。

Figure 1: Experimental study of the mixing performance in a curvilinear microchannel utilizing the EI and ET phenomena Groisman and Steinberg ( 2001 ) . (a) The experimental setup consisted of a curvilinear microchannel with two inlets and smoothly connected sixty half-rings (numbered 1, 2, .., 30)

实验结果

研究问题

• RQ1 如何利用弹性失稳与弹性湍流提升微流体器件中的混合效率？
• RQ2 在低雷诺数条件下，ET在微尺度热沉中提升传热速率的作用机制是什么？
• RQ3 驱替流体（如聚合物溶液）与被驱替流体（如非牛顿原油）的流变特性如何影响孔隙介质中ET驱动的原油驱替？
• RQ4 为何在涉及聚合物表面活性剂的体系中缺乏ET的孔隙尺度研究？这对EOR应用有何影响？
• RQ5 电驱动流动是否比压力驱动流动更有效地生成ET？其在微流体系统中具有哪些实际优势？

主要发现

• ET通过在低雷诺数下生成混沌流动结构，显著增强微流体系统中的混合效率，实现在无外部扰动下高效的质量传递。
• 电驱动ET由于具有塞状速度分布且无活动部件，是压力驱动系统的有前途替代方案，但实验验证仍有限。
• 在化学驱油（EOR）中，ET可通过促进流体混合并改变孔隙介质中的流动路径来提高原油驱替效率，但目前尚未在大规模中得到证实。
• 大多数ET在EOR中的研究忽略了原油的流变行为，而原油可能表现出剪切稀化、屈服应力和粘弹性，这些因素显著影响ET的发展与采收率。
• 关于聚合物类型、浓度与分子量如何影响ET生成的系统性研究严重缺乏，限制了工业EOR应用中的优化。
• 尽管在高雷诺数下对弹性惯性湍流（EIT）已有广泛研究，但ET向EIT的过渡路径仍研究不足；然而，近期模拟表明两者之间存在连续的线性失稳分支。

Figure 2: Mixing patterns of an ink drop placed at the center of a Couette-Taylor (CT) cell utilizing the ET phenomenon at different times Groisman and Steinberg ( 2004 ) in viscoelastic polymer solutions (a) and a Newtonian solvent (b).