BRIGE: Dynamically Tunable Nanostructured Surfaces for Multiphase Microfluidics

该奖项的研究目标是研究动态可调的纳米结构表面，以操纵多相微流体，用于芯片实验室，能源和热管理应用。纳米结构将在硅中制造，具有铁磁尖端，这样纳米结构的倾角将在磁场的作用下改变。实验研究将进行，以了解几何可调的纳米结构如何影响界面现象，表观接触角和表面张力。用于这些研究的技术将包括衍射限制显微镜、扫描电子显微镜和测角术。表征将旨在发展纳米结构倾角与液滴/气泡接触角之间的关系。随后将进行实验研究，以检查调节表面张力的能力，并根据需要促进微通道中的液滴/气泡离开。这项研究将为开发可调谐纳米结构提供新的方法，并为了解这些结构与液-气/蒸气界面的相互作用提供基本的认识。可调纳米结构表面的设计准则将获得，以实现控制液滴/气泡离开过程，这是许多微流体系统的主要挑战之一。此外，这些研究的结果将提供必要的框架、实验技术和知识，以允许研究相关的界面现象，如减少阻力的可调表面、定向液体扩散和排水、液滴操纵和液体约束。

The research objective of this award is to investigate dynamically tunable nanostructured surfaces to manipulate multi-phase microfluidics for lab-on-a-chip, energy, and thermal management applications. The nanostructures will be fabricated in silicon with ferromagnetic tips, such that the inclination of the nanostructures will change upon the application of a magnetic field. Experimental investigations will be performed to understand how geometrically tunable nanostructures affect interfacial phenomena, apparent contact angles, and surface tension forces. Techniques used for these studies will include diffraction limited microscopy, scanning electron microscopy, and goniometry. The characterizations will be aimed to develop a correlation between nanostructure inclination angle and droplet/bubble contact angles. Experimental studies will subsequently be performed to examine the ability to modulate surface tension and to promote droplet/bubble departure in microchannels on demand.The research will provide new methods to develop tunable nanostructures and fundamental understanding of the interactions of the liquid-air/vapor interface with these structures. Design guidelines for tunable nanostructured surfaces will be attained to achieve controlled droplet/bubble departure processes, which is one of the main challenges in many microfluidic systems. In addition, the results from these studies will provide the necessary framework, experimental techniques, and knowledge to allow investigations of related interfacial phenomena such as tunable surfaces for drag reduction, directional liquid spreading and draining, droplet manipulation, and liquid confinement.