This paper describes the pressure drop and local mass transfer in a rectangular microchannel having a width of 3.70 mm, height of 0.107 mm and length of 35 mm. The pressure measurements were carried out with distilled water as working fluid at Reynolds numbers in the range of 100-845, while mass tra
Pressure drop measurements in a microchannel
✍ Scribed by David Pfund; David Rector; Alireza Shekarriz; Aristotel Popescu; James Welty
- Publisher
- American Institute of Chemical Engineers
- Year
- 2000
- Tongue
- English
- Weight
- 728 KB
- Volume
- 46
- Category
- Article
- ISSN
- 0001-1541
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
Recent developments in micro‐energy and micro‐chemical systems have produced a need for greater understanding of flow in small channels. Several recent studies of friction factors and transition Reynolds numbers in rectangular microchannels have produced results that differ from classical theory. In this work, friction factors and laminar flow friction constants were determined for water flowing in high aspect ratio channels with depths ranging from 128 to 521 μm. Reynolds numbers were between 60 and 3,450. Pressure drops were measured within the channel itself to exclude entrance and exit losses. Transitions to turbulence were observed with flow visualization. Uncertainties in measured variables were quantified and propagated into the estimated friction constants. Friction factors were also determined in a 1,050‐μm‐deep channel that served as a control. After considering experimental uncertainties and systematic errors, significant differences remained between the results and classical theory.
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