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Title: Active Mixing in Microchannels using Surface Acoustic Wave Streaming on Lithium Niobate

Abstract

We present an active method for mixing fluid streams in microchannels at low Reynolds number with no dead volume. To overcome diffusion limited mixing in microchannels, surface acoustic wave streaming offers an extremely effective approach to rapidly homogenize fluids. This is a pivotal improvement over mixers based on complex 3D microchannels which have significant dead volume resulting in trapping or loss of sample. Our micromixer is integrable and highly adaptable for use within existing microfluidic devices. Surface acoustic wave devices fabricated on 128° YX LiNbO 3 permitted rapid mixing of flow streams as evidenced by fluorescence microscopy. Longitudinal waves created at the solid-liquid interface were capable of inducing strong nonlinear gradients within the bulk fluid. In the highly laminar regime (Re = 2), devices achieved over 93% mixing efficacy in less than a second. Micro-particle imaging velicometry was used to determine the mixing behavior in the microchannels and indicated that the liquid velocity can be controlled by varying the input power. Fluid velocities in excess of 3 cm•s -1 were measured in the main excitation region at low power levels (2.8mW). We believe that this technology will be pivotal in the development and advancement of microfluidic devices and applications.

Authors:
 [1];  [1];  [1];  [1]
  1. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Publication Date:
Research Org.:
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Sponsoring Org.:
USDOE National Nuclear Security Administration (NNSA)
OSTI Identifier:
1126940
Report Number(s):
SAND2005-7036
506502
DOE Contract Number:
AC04-94AL85000
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS

Citation Formats

Branch, Darren W., Meyer, Grant D., Bourdon, Christopher Jay, and Craighead, Harold G.. Active Mixing in Microchannels using Surface Acoustic Wave Streaming on Lithium Niobate. United States: N. p., 2005. Web. doi:10.2172/1126940.
Branch, Darren W., Meyer, Grant D., Bourdon, Christopher Jay, & Craighead, Harold G.. Active Mixing in Microchannels using Surface Acoustic Wave Streaming on Lithium Niobate. United States. doi:10.2172/1126940.
Branch, Darren W., Meyer, Grant D., Bourdon, Christopher Jay, and Craighead, Harold G.. Tue . "Active Mixing in Microchannels using Surface Acoustic Wave Streaming on Lithium Niobate". United States. doi:10.2172/1126940. https://www.osti.gov/servlets/purl/1126940.
@article{osti_1126940,
title = {Active Mixing in Microchannels using Surface Acoustic Wave Streaming on Lithium Niobate},
author = {Branch, Darren W. and Meyer, Grant D. and Bourdon, Christopher Jay and Craighead, Harold G.},
abstractNote = {We present an active method for mixing fluid streams in microchannels at low Reynolds number with no dead volume. To overcome diffusion limited mixing in microchannels, surface acoustic wave streaming offers an extremely effective approach to rapidly homogenize fluids. This is a pivotal improvement over mixers based on complex 3D microchannels which have significant dead volume resulting in trapping or loss of sample. Our micromixer is integrable and highly adaptable for use within existing microfluidic devices. Surface acoustic wave devices fabricated on 128° YX LiNbO3 permitted rapid mixing of flow streams as evidenced by fluorescence microscopy. Longitudinal waves created at the solid-liquid interface were capable of inducing strong nonlinear gradients within the bulk fluid. In the highly laminar regime (Re = 2), devices achieved over 93% mixing efficacy in less than a second. Micro-particle imaging velicometry was used to determine the mixing behavior in the microchannels and indicated that the liquid velocity can be controlled by varying the input power. Fluid velocities in excess of 3 cm•s-1 were measured in the main excitation region at low power levels (2.8mW). We believe that this technology will be pivotal in the development and advancement of microfluidic devices and applications.},
doi = {10.2172/1126940},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Nov 01 00:00:00 EST 2005},
month = {Tue Nov 01 00:00:00 EST 2005}
}

Technical Report:

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  • No abstract prepared.
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