The Optimal Elastic Flagellum

The optimal planar, periodic shape of a swimming slender body at zero Reynolds number. A swimming efficiency is maximized which is a ratio of the work required to drag the straightened filament through the fluid at the same velocity, to a combination of a hydrodynamic work and an elastic bending cost. The coefficient A_B measures the relative importance between the two (think elastic modulus), with A_B=0 corresponding to zero bending costs, and A_B=1 corresponding to extreme bending costs.

Category:

Science & Technology

Tags:

• Fluid dynamics
• swimming
• low Reynolds number
• elastic
• microorganism.

[SaverioIV]

Indeed it is swimming; there is no dragging, it moves by the zero-net force/torque conditions being satisfied. The passage of a waveform along a body is not time reversible (playing the movie backwards, you can tell the difference: the wave goes the other way!) So there is no problem with the Scallop theorem, for example, and swim it does.

[whatever3009]

is this thing swimming? it looks like its being dragged and in the process its producing sinusoid, if its swimming shouldnt it have time irreversible movement in its tail?

[whatever3009]

is this thing swimming? it looks like its being dragged and in the process its producing sinusoid, if its swimming shouldnt it have time irreversible movement in its tail?