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A theoretical and numerical approach to "magic angle" of stone skipping

Shin-ichiro Nagahiro·Yoshinori Hayakawa
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Abstract

We investigate oblique impacts of a circular disk and water surface. An experiment [ Clanet, C., Hersen, F. and Bocquet, L., Nature 427, 29 (2004) ] revealed that there exists a "magic angle" of 20 [deg.] between a disk face and water surface which minimize the required speed for ricochet. We perform 3-dimensional simulation of the water impacts using the Smoothed Particle Hydrodynamics (SPH) and analyze the results with an ordinal differential equation (ODE) model. Our simulation is in good agreement with the experiment. The analysis with the ODE model give us a theoretical insight for the ``magic angle" of stone skipping.

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Shin-ichiro Nagahiro, Yoshinori Hayakawa. 2004-11-25. A theoretical and numerical approach to "magic angle" of stone skipping. https://doi.org/10.1103/physrevlett.94.174501

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