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Granular Flow, Collisional Cooling and Charged Grains

D. E. Wolf·T. Scheffler·J. Schäfer
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Abstract

The non-Newtonian character of granular flow in a vertical pipe is analyzed. The time evolution of the flow velocity and the velocity fluctuations (or granular temperature) is derived. The steady state velocity has a power law dependence on the pipe width with an exponent between 3/4 and 3/2. The flow becomes faster the more efficient the collisional cooling is, provided the density remains low enough. The dependence of collisional cooling on the solid fraction, the restitution coefficient and a possible electric charge of all grains is discussed in detail.

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D. E. Wolf, T. Scheffler, J. Schäfer. 1999-09-14. Granular Flow, Collisional Cooling and Charged Grains. https://doi.org/10.1016/s0378-4371(99)00434-3

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