F. Alonso-Marroquin

Publications (2)2.26 Total impact

• Article: Bottlenecks in granular flow: when does an obstacle increase the flow rate in an hourglass?

  F Alonso-Marroquin, S I Azeezullah, S A Galindo-Torres, L M Olsen-Kettle
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  ABSTRACT: Bottlenecks occur in a wide range of situations from pedestrians, ants, cattle, and traffic flow to the transport of granular materials. We examine granular flow across a bottleneck using simulations of monodisperse disks. Contrary to expectations but consistent with previous work, we find that the flow rate across a bottleneck actually increases if an obstacle is optimally placed before it. Using the hourglass theory and a velocity-density relation, we show that the peak flow rate corresponds to a transition from free flow to congested flow, similar to the phase transition in traffic flow.
  Physical Review E 02/2012; 85(2 Pt 1):020301. · 2.26 Impact Factor
• Source

  Available from: ArXiv

  Article: Bottlenecks in granular flow: When does an obstacle increase the flowrate in an hourglass?

  F. Alonso-Marroquin, S. I. Azeezullah, S. A. Galindo-Torres, L. M. Olsen-Kettle
  [show abstract] [hide abstract]
  ABSTRACT: Bottlenecks occur in a wide range of applications from pedestrian and traffic flow to mineral and food processing. We examine granular flow across a bottleneck using particle-based simulations. Contrary to expectations we find that the flowrate across a bottleneck actually increases if an opti- mized obstacle is placed before it. The dependency of flowrate on obstacle diameter is derived using a phenomenological velocity-density relationship that peaks at a critical density. This relationship is in stark contrast to models of traffic flow, as the mean velocity does not depend only on density but attains hysteresis due to interaction of particles with the obstacle.
  09/2011;