Surface acoustic wave driven micro-flows: Flow control and transport of finite size particles

对少量流体的操作和对流体内部流动模式的详细控制是在被称为芯片实验室的微流控设备上成功处理生物和化学材料的先决条件。声表面波在压电衬底上产生的声流已被证明是一种在小体积流体中产生流动的有效且通用的方法。与研究较多的压力驱动的槽道内Poiseuille剪切流相比，声表面波产生的流型更为复杂，并且通常表现为一个或多个涡流。本项目的目标是利用和改进这些复杂的流型，并研究扩展颗粒在这种流场中的输运特性。

The manipulation of small amounts of fluids and a detailed control of the flow patterns within the fluid are preconditions for a successful processing of biological and chemical materials on microfluidic devices known as labs-on-a-chip. Acoustic streaming caused by surface acoustic waves on piezoelectric substrates has proved to be an efficient and versatile method to generate flows in small fluid volumes. In contrast to well investigated pressure driven Poiseuille type shear flows in channels, the surface acoustic wave generated stream patterns are more complex and typically display one or more vortices. It is the goal of this project to utilize and improve these complex flow patterns and to investigate the transport properties of extended particles in such flow fields.