Molecular diffusive scaling laws in pressure-driven microfluidic channels: deviation from one-dimensional Einstein approximations
| Autor: | Andrew Kamholz, Paul Yager |
|---|---|
| Rok vydání: | 2002 |
| Předmět: |
Convection
Scaling law Analyte geography geography.geographical_feature_category Chemistry Microfluidics Metals and Alloys Thermodynamics Mechanics Condensed Matter Physics Inlet Surfaces Coatings and Films Electronic Optical and Magnetic Materials Physics::Fluid Dynamics symbols.namesake Microfluidic channel Materials Chemistry symbols Duct (flow) Electrical and Electronic Engineering Einstein Instrumentation |
| Zdroj: | Sensors and Actuators B: Chemical. 82:117-121 |
| ISSN: | 0925-4005 |
| DOI: | 10.1016/s0925-4005(01)00990-x |
| Popis: | This study presents a theoretical analysis of the scaling laws for analyte diffusion in a microfluidic chemical analysis device, the T-sensor. Because the flow is pressure-driven, the velocity profile is non-uniform, inducing a distribution in residence time among analyte molecules. Solutions for concentration distribution are given from the device inlet to a downstream distance where variations in the scaling law become negligible. All data were generated using a custom two-dimensional model that describes convection and diffusion in a system of two fluids running side-by-side in a duct. These results deviate substantially from those expected by simpler calculations, including a one-dimensional model. This study lends a better understanding of the transport of analytes diffusing in microchannels and provides a means for determining whether the complicated effects need to be considered in device design and operation. |
| Databáze: | OpenAIRE |
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