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

Figure 9

(a) Helicoidal biofilm streamers with different helicoidal size steps in cylindrical channels in diameters of 1 mm and 2 mm. (b) The spiral shape of the contour of minimum stain rate near the inner wall of the cylindrical channel (upward view). (c) Schematic of the line joining points of the minimal shear stress on different circular cross sections of the channel. (d) The spiral-like biofilm streamer in the cylindrical channel projected on a Y-Z flat surface. (e) An enlarged region of the helicoidal biofilm streamers, the blue line with circular points and the red line with red square points indicate biofilm streamers, formed in channels with diameters of 1 mm and 2 mm under the same volumetric flow rate and angular rotation velocity; the red line with circular points and the red line with red triangular points indicate helicoidal biofilm streamers formed in the same diameter channels but under different angular rotation velocities.

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