Publications [#245588] of Robert P. Behringer

Papers Published
  1. Pak, HK; Doorn, EV; Behringer, RP, Ambient gases and heaping instability of granular materials under vertical vibration, International Journal of Bifurcation and Chaos in Applied Sciences and Engineering, vol. 7 no. 5 (1997), pp. 1035-1041 .

    We consider layers of non-cohesive granular materials lying on a vertically vibrating surface. Above a threshold acceleration, Γ = Γc, internal convective motion begins, and the free surface of the granular material becomes unstable to the formation of a heap. As Γ increases further, there are several higher order instabilities, traveling surface waves, subharmonic bifurcations, and bubbling. We find that for particles of diameter d ≤ 1 mm, the pressure P of the surrounding gas plays a key role in the instabilities. We propose criteria to determine when gas effects are relevant.