Abstract:
Sperm are known to exhibit two distinct types of motility. One is characterized by constant amplitude, symmetrical waveforms. The other is characterized by asymmetrical waveforms, corresponding to an increase in calcium concentration within the flagellum. The goal of this work is to model sperm swimming in a viscous, incompressible fluid using the method of regularized Stokeslets. The mechanical forces are due to passive stiffness properties and active bending moments are a function of the local calcium concentration. Results showing emergent waveforms, swimming speeds, and trajectories will be compared to experimental data. The hydrodynamic interactions of multiple sperm will also be presented and compared to experimental data, where sperm trains and vortices are often seen. Time permitting, a new regularized Stokes formulation for a Kirchhoff rod will be presented.