BA9 


Biological and Active Matters


Symmetric shear banding and swarming vortices in bacterial "superfluids"


October 15, 2018 (Monday) 2:45


Track 6 / Tanglewood

(Click on name to view author profile)

  1. Cheng, Xiang (University of Minnesota, Chemical Engineering and Materials Science)
  2. Guo, Shuo (University of Minnesota, Chemical Engineering and Materials Science)
  3. Samanta, Devranjan (Indian Institute of Technology, Ropar, Mechanical Engineering)
  4. Peng, Yi (University of Minnesota, Chemical Engineering and Materials Science)
  5. Xu, Xinliang (Beijing Computational Science Research Center)

(in printed abstract book)
Xiang Cheng1, Shuo Guo1, Devranjan Samanta2, Yi Peng1, and Xinliang Xu3
1Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN 55455; 2Mechanical Engineering, Indian Institute of Technology, Ropar, Ropar, India; 3Beijing Computational Science Research Center, Beijing, China


Cheng, Xiang


Bacterial suspensions can flow without apparent viscosity. Such a superfluid-like behavior stems from the collective motions of swimming bacteria. Here, we explore the microscopic flow profile of bacterial "superfluids" under simple shear. We find that, instead of deforming uniformly, bacterial "superfluids" develop multiple shear bands, i.e., regions with different shear deformations. We construct a simple model that quantitatively describes the shape of the shear-banding structure and reveals important physical properties of collective bacterial motions. Our study sheds light on complex interactions between swimming microorganisms and ambient fluid flows, crucial for the survival of microorganisms in nature and the manipulation of bacterial suspensions in engineering settings.