Howell Peter B, Mott David R, Golden Joel P, Ligler Frances S
Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, Washington DC 20375-5348, USA.
Lab Chip. 2004 Dec;4(6):663-9. doi: 10.1039/b407170k. Epub 2004 Nov 11.
A mixer, based on the Dean vortex, is fabricated and tested in an on-chip format. When fluid is directed around a curve under pressure driven flow, the high velocity streams in the center of the channel experience a greater centripetal force and so are deflected outward. This creates a pair of counter-rotating vortices moving fluid toward the inner wall at the top and bottom of the channel and toward the outer wall in the center. For the geometries studied, the vortices were first seen at Reynolds numbers between 1 and 10 and became stronger as the flow velocity is increased. Vortex formation was monitored in channels with depth/width ratios of 0.5, 1.0, and 2.0. The lowest aspect ratio strongly suppressed vortex formation. Increasing the aspect ratio above 1 appeared to provide improved mixing. This design has the advantages of easy fabrication and low surface area.
一种基于迪恩涡的微混合器以片上形式制造并进行了测试。当流体在压力驱动流作用下绕曲线流动时，通道中心的高速流体会受到更大的向心力，从而向外偏转。这会产生一对反向旋转的涡旋，将流体向通道顶部和底部的内壁移动，并向通道中心的外壁移动。对于所研究的几何形状，涡旋首先出现在雷诺数介于1和10之间，并且随着流速的增加而变强。在深度/宽度比为0.5、1.0和2.0的通道中监测涡旋形成。最低的纵横比强烈抑制了涡旋的形成。将纵横比增加到1以上似乎能改善混合效果。这种设计具有易于制造和表面积小的优点。
