Effects of poiseuille flows on swimming of magnetic helical robots in circular channels

Official URL: http://dx.doi.org/10.1007/s10404-015-1629-6

This study reports experimental and numerical model results on swimming of microswimmers inside circular channels. Designed to mimic the swimming behavior of biological organisms at low Reynolds number flows, a number of microswimmers are manufactured utilizing a 3D printer and consist of a helical tail and a body that encapsulates a small magnet. The swimming motion results from the synchronized rotation of the artificial swimmer with the rotating magnetic field induced by three electromagnetic-coil pairs. In order to obtain linear and angular velocities and to analyze the motion of the microswimmer, a computational model is developed to obtain swimmer velocities from the solutions of three-dimensional steady Stokes equations which govern the flow around the swimmers inside the channel. Experiments and numerical simulations are carried out for a number of configurations with different geometric parameters and flow rates in the channel filled with glycerol. Numerical results agree well with experimentally measured average velocities of swimmers. Results describe the influence of the flow rate, length of the tail, diameter of the channel, and the direction of the rotation of the swimmer on the velocity and trajectories of microswimmers.