Observation of fluidic behavior in a polymethylmethacrylate-fabricated microchannel by a simple spectroscopic analysis

An easy-to-use and low cost microreactor made of polymethylmethacrylate was mechanically fabricated with a microchannel (200 mum x 200 mum). The laminar flow behavior was investigated by visualizing the flow of red and green aqueous solutions. Digitized color images from a CCD camera were analyzed by resolving the color in RGB mode. Numeric data from red and green color components in the images could reveal the fluidic behavior in the microchannel because the spatial spectroscopic information corresponds to the color solution flows. Effects of corner shapes in a turn, flow rate and surface roughness were observed on the mixing of the laminar flows. A right angle turn and unevenness of +/-10% of the inner wall surface almost mixed the two color laminar flows.