Swimming by reciprocal motion at low Reynolds number
Citations Over TimeTop 1% of 2014 papers
Abstract
Biological microorganisms swim with flagella and cilia that execute nonreciprocal motions for low Reynolds number (Re) propulsion in viscous fluids. This symmetry requirement is a consequence of Purcell's scallop theorem, which complicates the actuation scheme needed by microswimmers. However, most biomedically important fluids are non-Newtonian where the scallop theorem no longer holds. It should therefore be possible to realize a microswimmer that moves with reciprocal periodic body-shape changes in non-Newtonian fluids. Here we report a symmetric 'micro-scallop', a single-hinge microswimmer that can propel in shear thickening and shear thinning (non-Newtonian) fluids by reciprocal motion at low Re. Excellent agreement between our measurements and both numerical and analytical theoretical predictions indicates that the net propulsion is caused by modulation of the fluid viscosity upon varying the shear rate. This reciprocal swimming mechanism opens new possibilities in designing biomedical microdevices that can propel by a simple actuation scheme in non-Newtonian biological fluids.
Related Papers
- → Deformation and breakup of stretching bridges of Newtonian and shear-thinning liquids: comparison of one- and two-dimensional models(2001)137 cited
- → Study and Analysis of Non-Newtonian Fluid Speed Bump(2023)1 cited
- → Shear rate dependent viscosity of suspensions in newtonian and non-newtonian liquids(1974)84 cited
- → INTER-LABORATORY MEASUREMENTS OF THE VISCOUS PROPERTIES OF NEWTONIAN AND NON-NEWTONIAN FLUIDS WITH THE FALLING NEEDLE VISCOMETER(2023)
- → On the energy equality for solutions to Newtonian and non-Newtonian fluids(2019)