Department of Mechanical Engineering, University of California Santa Barbara, CA 93106, USA.
Lab Chip. 2010 May 7;10(9):1148-52. doi: 10.1039/b919942j. Epub 2010 Feb 9.
A scaling model is presented for low Reynolds number viscous flow within an array of microfabricated posts. Such posts are widely used in several lab-on-a-chip applications such as heat pipes, antibody arrays and biomolecule separation columns. Finite element simulations are used to develop a predictive model for pressure driven viscous flow through posts. The results indicate that the flow rate per unit width scales as approximately h1.17g1.33/d0.5 where h is the post height, d post diameter and g is the spacing between the posts. These results compare favorably to theoretical limits. The scaling is extended to capillary pressure driven viscous flows. This unified model is the first report of a scaling that incorporates both viscous and capillary forces in the microfabricated post geometry. The model is consistent with Washburn dynamics and was experimentally validated to within 8% using wetting on microfabricated silicon posts.
提出了一种用于微制造柱列内低雷诺数粘性流的标度模型。这种柱子广泛应用于几种微流控芯片应用中，如热管、抗体阵列和生物分子分离柱。有限元模拟用于开发通过柱子的压力驱动粘性流的预测模型。结果表明，单位宽度的流速约为 h1.17g1.33/d0.5，其中 h 是柱子的高度，d 是柱子的直径，g 是柱子之间的间距。这些结果与理论极限值吻合较好。该标度扩展到毛细管压力驱动的粘性流。这种统一的模型首次报告了在微制造柱几何形状中同时包含粘性和毛细作用力的标度。该模型与 Washburn 动力学一致，并使用微制造硅柱上的润湿在 8%的范围内进行了实验验证。
