Coefficient of restitution of colliding viscoelastic spheres

Rosa Ramírez, Thorsten Poschel, Nikolai V. Brilliantov, and Thomas Schwager

Phys. Rev. E 60 4465-4472 (1999)

Index


Abstract

We perform a dimension analysis for colliding viscoelastic spheres to show that the coefficient of normal restitution $\epsilon$ depends on the impact velocity $g$ as $\epsilon=1-\gamma_1 g^{1/5}+\gamma_2g^{2/5}\mp\dots$, in accordance with recent findings. We develop a simple theory to find explicit expressions for coefficients $\gamma_1$ and $\gamma_2$. Using these and few next expansion coefficients for $\epsilon(g)$ we construct a Pad\'e-approximation for this function which may be used for a wide range of impact velocities where the concept of the viscoelastic collision is valid. The obtained expression reproduces quite accurately the existing experimental dependence $\epsilon(g)$ for ice particles.
             Molecular Dynamics and Kinetic Theory Group
             Physics Department

      Facultad de Ciencias Físicas y Matemáticas
Universidad de Chile