Rayleigh-Taylor Instability, Non-Newtonian Rheology, and Chain Of Bubbles in Polymer Solutions

聚合物溶液中的瑞利-泰勒不稳定性、非牛顿流变学和气泡链

• 批准号: 0325743
• 负责人: Igor Kliakhandler
• 金额: $ 7万
• 依托单位: Michigan Technological University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-02-15 至 2006-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0325743&HistoricalAwards=false
• 关键词: Rayleigh; Taylor; Instability; Non; Newtonian

AbstractCTS-0325743I. Kliakhandler, Michigan Technological UniversityRayleigh-Tayler Instability, Non-Newtonian Rheology, and Chain of Bubbles in Polymer SolutionsThe motion of bubbles in a liquid is one of the major fields in hydrodynamics. It was studied already by Leonardo da Vinci, who noticed sinuous movement of rising bubbles, which is relatively easy to observe in long columns. The available body of knowledge and even its language connotation consider bubbles only as a discrete, detached from each other, units. The continuous jet of air in Newtonian liquids produces usual bubbling through Rayleigh-Taylor instability of the jet.In the recent work by PI it was found that in concentrated polymer solutions bubbles may form a qualitatively new structures. The development of Rayleigh-Taylor instability may be arrested by elastic properties of the polymer solutions. As a result, instead of individual bubbles, a long chain of bubbles is formed. The bubbles in the chain are very stable, slowly rising, connected by thin necks; the whole structure is similar to beads, or bubble "sausage"; see figures 1, 2 on the next pages. The rheological properties of polymeric solutions where it is possible to create the chain of bubble are quite interesting and call for their careful study.So far, even the general understanding of this unusual and interesting phenomenon is incomplete. Many basic questions about the chain of bubbles arise; no modeling of the phenomenon has yet been done.The proposed research will be devoted to the study and modeling of chain of bubbles dynamics, and will concentrate on the few main issues; rheology of polymers used in the formation of the chain, experimental elucidation of conditions necessary for the creation of chain of bubbles, analysis of stability of the air jet for various conditions, and strongly nonlinear modeling of the phenomenon.

Abstractcts-0325743i。 Kliakhandler，密歇根州技术大学雷利 - 泰勒，非牛顿流变学和聚合物溶液中气泡链液体中的气泡运动是流体动力学的主要领域之一。 莱昂纳多·达·芬奇（Leonardo da Vinci）已经对其进行了研究，他注意到了上升气泡的弯曲运动，这在长柱中相对容易观察。 可用的知识体系，甚至其语言内涵仅将泡沫视为一个离散的泡沫，彼此分离，单位。 牛顿液体中的空气连续射流会产生通常通过射流的雷利 - 泰勒不稳定的气泡。 雷利 - 泰勒不稳定性的发展可能会被聚合物溶液的弹性特性所捕捉。 结果，形成了一系列气泡，而不是单个气泡。 链中的气泡非常稳定，缓慢上升，由细颈部连接。整个结构类似于珠子或气泡“香肠”；请参阅下一页上的图1、2。 可以创建气泡链的聚合解决方案的流变特性非常有趣，并需要他们仔细的研究。因此，即使对这种不寻常且有趣的现象的一般理解也不完整。 关于气泡链的许多基本问题出现了；尚未对该现象进行建模。拟议的研究将致力于对气泡动力学链的研究和建模，并将集中在少数主要问题上。用于形成链形成的聚合物的流变学，生成气泡链所必需的条件的实验阐明，在各种条件下对空气射流的稳定性分析以及现象的强烈非线性建模。