J. Fluid Mech., 273, 189-211, 1994.

Movement of magnetic bacteria in time varying magnetic fields

Bernhard Steinberger, Nikolai Petersen, Harald Petermann, and Dieter G. Weiss


Abstract

The magnetic moment of magnetic bacteria was determined by motion analysis in a time-dependent magnetic field. In order to do this, we had to know the drag which was exerted on the moving bacterium by the surrounding liquid. In a first approximation the bacterium was supposed to be an ellipsoid. In order to determine drag coefficients for more complicated (and realistic) forms, a model experiment was built. In this experiment enlarged models of bacteria were rotated in a viscous liquid and the torque acting upon them was measured. Furthermore, computing algorithms were developed in order to calculate drag coefficients of magnetic bacteria and to simulate their motion in magnetic fields.