Simultaneous, volumetric temperature and velocity field measurements within and around micro-droplets for the analysis and characterization of disperse multiphase flows in microfluidic Lab-on-a-Chip systems

对微液滴内部和周围进行同步体积温度和速度场测量，用于分析和表征微流体芯片实验室系统中的分散多相流

• 批准号: 407463169
• 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: 2019
• 资助国家: 德国
• 起止时间: 2018-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/407463169?language=en
• 关键词: Simultaneous; volumetric; temperature; velocity; field

In recent years, microfluidic analysis systems have gained considerable interest in various scientific and industrial fields such as medical technology, pharmacy, chemistry, biology, process engineering, etc.. Particularly microfluidic platforms based on so-called droplet microfluidics have experienced a surge in applications. In these systems, samples are introduced into liquid droplets with volumes ranging from a few microliters to femtoliters, which are surrounded by an insoluble phase and analyzed in the microchannel. This results in considerable reductions in the amount of samples or reactants required and in process time, which can save a large part of the associated costs. An essential step in these procedures is the manipulation and sorting of the various droplets, whereby precise control of the droplet dynamics is crucial for the effectiveness of the analysis platform. An efficient and frequently applied method is the use of Marangoni-forces, which are often induced by producing temperature gradients at the droplet interface, for example with of a focused laser beam. At present, however, the fluid mechanical phenomena that determine the droplet behavior in the microchannel are not yet sufficiently understood. For this reason, a detailed experimental analysis and characterization of the three-dimensional and transient flow phenomena arising from the manipulation of a droplet in a microchannel will be performed within this research project. For this purpose, advanced optical measurement methods will be utilized which enable the simultaneous measurement of the three-dimensional flow field and the three-dimensional temperature field in and around individual droplets with high resolution an accuracy. The results will lead to an improved understanding of the fundamental fluid mechanics that control the droplet behavior and thus contribute to a further increase in efficiency and distribution of these lab-on-a-chip systems.

近年来，微流控分析系统在医疗技术、制药、化学、生物学、工艺工程等各个科学和工业领域引起了极大的兴趣。特别是基于所谓的微滴微流控技术的微流控平台，在应用方面出现了激增。在这些系统中，样品被引入体积从几微升到飞升不等的液滴中，液滴被不溶相包围，并在微通道中进行分析。这大大减少了所需样品或反应物的数量和处理时间，从而节省了大部分相关成本。这些程序中的一个重要步骤是对各种液滴的操作和分类，因此液滴动力学的精确控制对分析平台的有效性至关重要。一种有效且常用的方法是使用马兰戈尼力，它通常通过在液滴界面产生温度梯度来诱导，例如使用聚焦激光束。然而，目前，决定微通道中液滴行为的流体力学现象尚未得到充分的了解。因此，本研究项目将对微通道中液滴的操纵所产生的三维和瞬态流动现象进行详细的实验分析和表征。为此，将采用先进的光学测量方法，以高分辨率和精度同时测量单个液滴内部和周围的三维流场和三维温度场。研究结果将有助于提高对控制液滴行为的基本流体力学的理解，从而有助于进一步提高这些芯片实验室系统的效率和分布。