Simulations of surface tension driven flows and interactions between fluid flow and solid particles

模拟表面张力驱动的流动以及流体流动与固体颗粒之间的相互作用

• 批准号: 0808129
• 负责人: Francois Blanchette
• 金额: $ 13.3万
• 依托单位: University of California - Merced
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-07-01 至 2012-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0808129&HistoricalAwards=false
• 关键词: Simulations; surface; tension; driven; flows

This proposal focuses on multiphase flows. The first part of the project is a study of fluid-fluid interfaces which, on small scales, are dominated by surface tension. Such flows are relevant to the dynamics of emulsions, bubbles, drops and micro-fluidic devices. Highly accurate numerical simulations will be employed to describe the dynamics of drops merging or forced through micro-pipes. A novel approach to direct simulations of spatially varying surface tension will be presented. The simulations will be used to explore the potential of Marangoni flows to generate mixing in micro-drops. The second part of the project is concerned with interactions between small solid particles and their surrounding fluid, which are determinant in a variety of natural systems such as rivers, oceans, and the atmosphere. Numerical simulations will explore the mechanism by which particulate matter is eroded by an overlying fluid. The capacity of settling particles to transport heat in an advective rather than diffusive manner, without generating large scale fluid motion, will also be examined. The overall goal is to develop tools to investigate these complex physical systems and extract a fundamental understanding of basic phenomena at play in multiphase flows.The research described in this proposal will be conducted at Merced, the newest campus (opened in 2005) of the University of California. It is the only research university of the Central Valley, and the student body is both diverse and traditionally under-represented at the university level. This project will provide research opportunities to both undergraduate and graduate students. The first topic studied involves the interaction of liquids and gases with other liquids, as is the case in drops and bubbles. Special emphasis will be placed on obtaining an understanding of the behavior of drops in the presence of temperature variations in ?lab-on-a- chip? systems, which allow controlled reactions to be studied on the micron scale. A second field of study will be the interaction of fluids with small solid particles, such as sand and sediments. The mechanism by which fluid flow can erode deposited particles, and the capacity of settling particles to affect heat transport will be investigated in detail. Broadly applicable new techniques will be developed to simulated these systems accurately and efficiently.

该建议侧重于多相流。该项目的第一部分是研究流体-流体界面，在小尺度上，该界面由表面张力主导。这种流动与乳液、气泡、液滴和微流体装置的动力学有关。高度精确的数值模拟将被用来描述液滴合并或被迫通过微管道的动力学。一种新的方法来直接模拟空间变化的表面张力。模拟将被用来探索马兰戈尼流的潜力，以产生混合的微滴。该项目的第二部分涉及小固体颗粒与其周围流体之间的相互作用，这些相互作用在各种自然系统中具有决定性作用，如河流，海洋和大气。数值模拟将探索颗粒物质被上覆流体侵蚀的机制。 沉降颗粒以平流而不是扩散方式输送热量的能力，而不产生大规模的流体运动，也将被检查。 总体目标是开发工具来调查这些复杂的物理系统，并提取在多相流中起作用的基本现象的基本理解。本提案中所描述的研究将在加州大学最新校区（2005年开放）默塞德进行。它是中央谷唯一的研究型大学，学生群体多样，传统上在大学一级代表性不足。这个项目将为本科生和研究生提供研究机会。 研究的第一个主题涉及液体和气体与其他液体的相互作用，如液滴和气泡。特别强调的是将放在获得在温度变化的存在下，在下降的行为的理解？芯片实验室系统，允许在微米尺度上研究受控反应。第二个研究领域将是流体与小固体颗粒（如沙子和沉积物）的相互作用。将详细研究流体流动侵蚀沉积颗粒的机制，以及沉降颗粒影响热传输的能力。将开发广泛适用的新技术来准确有效地模拟这些系统。