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.

Top



See also...

Numerical Bifurcation Methods and their Application to Fluid Dynamics : Analysis beyond Simulation

H.A. Dijkstra, F.W. Wubs, A.K. Cliffe, E. Doedel, I.F. Dragomirescu, B. Eckhardt, A.Y. Gelfgat, A.L. Hazel, V. Lucarini, A.G. Salinger, E.T. (...) 

> More...

Prediction of the dynamics of a backward-facing step flow using focused time-delay neural networks and particle image velocimetry data-sets

By Antonios Giannopoulos, Jean-Luc Aider in International Journal of Heat and Fluid Flow The objective of this experimental work was to evaluate (...) 

> More...

 

Practical information

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