Turning bacterial suspensions into a "superfluid"

H.M. Lopez, J. Gachelin, C. Douarche, H.Auradou, E. Clément ; Phys. Rev. Lett., 115, 28301, (2015)

The rheological response under simple shear of an active suspension of Escherichia coli is determined in a large range of shear rates and concentrations. The effective viscosity and the time scales characterizing the bacterial organization under shear are obtained. In the dilute regime, we bring evidence for a low-shear Newtonian plateau characterized by a shear viscosity decreasing with concentration. In the semidilute regime, for particularly active bacteria, the suspension displays a “superfluidlike” transition where the viscous resistance to shear vanishes, thus showing that, macroscopically, the activity of pusher swimmers organized by shear is able to fully overcome the dissipative effects due to viscous loss.

Haut de page



À lire aussi...

Review article : On the diverse roles of fluid dynamic drag in animal swimming and flying

R. Godoy-Diana & B. Thiria. J. Roy. Soc. Interface 15 20170715 (2018) [doi:10.1098/rsif.2017.0715] When a body moves through a fluid, drag is (...) 

> Lire la suite...

Synchronisation and collective swimming patterns in Hemigrammus bleheri

I. Ashraf, R. Godoy-Diana, J. Halloy, B. Collignon, B. Thiria Journal of the Royal Society Interface 13 20160734 (2016) In this work, we address (...) 

> Lire la suite...

 

Informations Pratiques

Laboratoire : 01 40 79 45 22
Directeur : Philippe Petitjeans
Administratrice : Frédérique Auger (01 40 79 45 22)
Gestionnaire : Claudette Barez (01 40 79 58 53)
Courriel : dir (arobase) pmmh.espci.fr

Nous rendre visite