TY - JOUR
T1 - Energy transport in a concentrated suspension of bacteria
AU - Ishikawa, T.
AU - Yoshida, N.
AU - Ueno, H.
AU - Wiedeman, M.
AU - Imai, Y.
AU - Yamaguchi, T.
PY - 2011/7/7
Y1 - 2011/7/7
N2 - Coherent structures appear in a concentrated suspension of swimming bacteria. While transport phenomena in a suspension have been studied extensively, how energy is transported from the individual cell scale to the larger mesoscale remains unclear. In this study, we carry out the first successful measurement of the three-dimensional velocity field in a dense suspension of bacteria. The results show that most of the energy generated by individual bacteria dissipates on the cellular scale. Only a small amount of energy is transported to the mesoscale, but the gain in swimming velocity and mass transport due to mesoscale coherent structures is enormous. These results indicate that collective swimming of bacteria is efficient in terms of energy. This paper sheds light on how energy can be transported toward smaller wave numbers in the Stokes flow regime.
AB - Coherent structures appear in a concentrated suspension of swimming bacteria. While transport phenomena in a suspension have been studied extensively, how energy is transported from the individual cell scale to the larger mesoscale remains unclear. In this study, we carry out the first successful measurement of the three-dimensional velocity field in a dense suspension of bacteria. The results show that most of the energy generated by individual bacteria dissipates on the cellular scale. Only a small amount of energy is transported to the mesoscale, but the gain in swimming velocity and mass transport due to mesoscale coherent structures is enormous. These results indicate that collective swimming of bacteria is efficient in terms of energy. This paper sheds light on how energy can be transported toward smaller wave numbers in the Stokes flow regime.
UR - http://www.scopus.com/inward/record.url?scp=79961083252&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=79961083252&partnerID=8YFLogxK
U2 - 10.1103/PhysRevLett.107.028102
DO - 10.1103/PhysRevLett.107.028102
M3 - Article
C2 - 21797644
AN - SCOPUS:79961083252
VL - 107
JO - Physical Review Letters
JF - Physical Review Letters
SN - 0031-9007
IS - 2
M1 - 028102
ER -