Investigations of particle dynamics and their interaction with the carrying flow in micro systems

粒子动力学及其与微系统中载流相互作用的研究

• 批准号: 209009089
• 负责人: Professor Dr. Christian Joachim Kähler
• 金额: --
• 依托单位: Institut für Strömungsmechanik und Aerodynamik (LRT-7)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2011
• 资助国家: 德国
• 起止时间: 2010-12-31 至 2017-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/209009089?language=en
• 关键词: Investigations; particle; dynamics; their; interaction

Multiphase flows are complex systems in which a liquid drags other components in gaseous, liquid or solid state. They are ubiquitous in nature and industrial processes and they are one of the most scientific challenges in fluid physics. On the other hand, the new miniaturization techniques permit to reduce the size of many fluidic systems of interest, but they require a deeper understanding on how multi-phasic flows behave at these scales. One of the biggest questions in this field is the stability of the flow and the transition to chaos and turbulence. Microfluidic flows do not enter in turbulent regimes, but some authors have suggested that micro-multi-phasic flows might enter into chaotic flow regimes regardless the scale of the system. However, the topic has not been studied in detail in confined systems. Our first results reveal interesting patterns that need to be studied in more detail. Directly related with small scale systems is the problem of clogging, specially when dealing with suspensions in microfluidic devices. Surprisingly, the topic has only been treated marginally in the literature on microfluidics. Our aim is to find the analogies with the well-known problem of silo clogging or arching in dry granular system, and apply similar techniques to unclog or to prevent the clogging.

多相流是一种复杂的系统，其中液体拖曳气态、液态或固态的其他组分。它们在自然界和工业过程中无处不在，是流体物理学中最具科学性的挑战之一。另一方面，新的小型化技术允许减小许多感兴趣的流体系统的尺寸，但它们需要更深入地理解多相流在这些尺度下的行为。这一领域最大的问题之一是流动的稳定性以及向混沌和湍流的过渡。微流体流动不会进入湍流状态，但一些作者提出，无论系统的规模如何，微多相流都可能进入混沌流状态。然而，该主题尚未在受限系统中详细研究。我们的第一个结果揭示了有趣的模式，需要更详细地研究。与小规模系统直接相关的是堵塞问题，特别是当处理微流体装置中的悬浮液时。令人惊讶的是，这个话题在微流体的文献中只被边缘化。我们的目的是找到与干燥颗粒系统中众所周知的筒仓堵塞或堵塞问题的相似之处，并应用类似的技术来疏通或防止堵塞。