Abstract:
:In most environments, such as natural aquatic systems, bacteria are found predominantly in self-organized sessile communities known as biofilms. In the presence of a significant flow, mature multispecies biofilms often develop into long filamentous structures called streamers, which can greatly influence ecosystem processes by increasing transient storage and cycling of nutrients. However, the interplay between hydrodynamic stresses and streamer formation is still unclear. Here, we show that suspended thread-like biofilms steadily develop in zigzag microchannels with different radii of curvature. Numerical simulations of a low-Reynolds-number flow around these corners indicate the presence of a secondary vortical motion whose intensity is related to the bending angle of the turn. We demonstrate that the formation of streamers is directly proportional to the intensity of the secondary flow around the corners. In addition, we show that a model of an elastic filament in a two-dimensional corner flow is able to explain how the streamers can cross fluid streamlines and connect corners located at the opposite sides of the channel.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Rusconi R,Lecuyer S,Autrusson N,Guglielmini L,Stone HAdoi
10.1016/j.bpj.2011.01.065subject
Has Abstractpub_date
2011-03-16 00:00:00pages
1392-9issue
6eissn
0006-3495issn
1542-0086pii
S0006-3495(11)00183-4journal_volume
100pub_type
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