Open AccessExperimental study of flow characteristics in rough microchannels
Author(s) -
Pengfei Hao,
Zhaohui Yao,
Feng He
Publication year - 2007
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.56.4728
Subject(s) - laminar flow , materials science , drag , mechanics , surface finish , turbulence , particle image velocimetry , surface roughness , flow (mathematics) , optics , composite material , physics
The effect of surface roughness on the frictional characteristics of the liquid flow in the microchannels with distributed rectangular roughness elements is experimentally studied. The velocity fields are obtained by micro particle image velocimetry (micro-PIV). The friction coefficients in the microchannels with 3%—7% relative roughness are higher than the prediction based on the conventional theory due to the additional pressure drag caused by roughness elements. The existence of roughness elements gives rise to additional disturbance in the laminar stream, and the early transition to turbulent flow in the rough microchannels is validated.