Dynamics of Granular Flow through a Vertical Pipe under the Control of Inflow Rate

Abstract

We present experimental results regarding the dynamical property of granular flow through a vertical glass pipe under the control of inflow rate. It was found that there exists a critical inflow rate for the formation of density waves. The power spectrum of the density waves exhibits clear power-law behavior, S( f) ∼ f^-α, with α\simeq 4/3. This value of α is robust under variation of inflow rate.