Abstract
The size of microfluidic channels prevents the use of conventional methods for flow velocity measurement. This paper presents and evaluates a method of flow velocity measurement using a temperature dependent fluorescent dye and a microheater. The microheater applied a heat pulse to the dye flowing in a glass capillary, resulting in a plug of fluid of lower fluorescent intensity. By tracking this low intensity region, the velocity of the heat pulse travelling with the flow was determined and used to calculate average flow velocity using correlations. The method was verified by measuring a range of flow velocities in two different sized glass capillaries.
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Acknowledgment
Financial support from the National Sciences and Engineering Research Council (NSERC) of Canada, through a research grant to D. Li, is gratefully acknowledged.
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Fu, R., Li, D. Flow velocity measurement in microchannels using temperature-dependent fluorescent dye. Microfluid Nanofluid 3, 27–32 (2007). https://doi.org/10.1007/s10404-006-0102-y
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DOI: https://doi.org/10.1007/s10404-006-0102-y