Wolf, D.E; Scheffler, T; Schäfer, J - In: Physica A: Statistical Mechanics and its Applications 274 (1999) 1, pp. 171-181
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....