A Particle Model of Rolling Grain Ripples Under Waves

@article{Andersen1999APM,
  title={A Particle Model of Rolling Grain Ripples Under Waves},
  author={Ken Haste Andersen},
  journal={Physics of Fluids},
  year={1999},
  volume={13},
  pages={58-64}
}
A simple model for the formation of rolling grain ripples on a flat sand bed by the oscillatory flow generated by a surface wave is presented. An equation of motion is derived for the individual ripples, seen as “particles,” on the otherwise flat bed. The model accounts for the initial appearance of the ripples, the subsequent coarsening of the ripples, and the final equilibrium state. The model is related to the physical parameters of the problem, and an analytical approximation for the… 

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