The Mechanical Analysis of the Biofilm Streamer Nucleation and Geometry Characterization in Microfluidic Channels

Figure 11

(a) Bacterial streamers developed in the channels after 12 h at constant flow rate (corresponding to an average speed of 0.75 μL/min) for two different experiments. The flow direction is from left to right. Bacteria are fluorescently labeled, and images of the middle plane of the channel are taken with a confocal microscope. Scale bars, 100 μm. (b) Numerical results of the modulus of the velocity field in a plane at 1/4 of the channel height from the upper surface. Coordinate system () and color scale are shown. (c) Flow components perpendicular to the primary flow (represented here with streamlines) in the same plane as (b). Red and blue colors indicate here velocity components orthogonal to the plane of the channel, directing, respectively, upwards (positive y) and downwards (negative y). (d) Perspective view of the channel showing pairs of counterrotating vertices in cross-sectional planes right before and after the turns. (e) A cross section of the channel, right after a turn.

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