Pedestrian channel flow at a bottleneck is investigated under the open boun
daries by using the lattice-gas model of biased random walkers. It is shown
that a dynamical phase transition occurs from the free flow to the choking
Row at a critical density p, with increasing density. The flow rate satura
tes at higher density than the critical density. In the choking-few region,
a scaling behavior is found as follows: the saturated flow rate J(Delta) s
cales as J(s) x d(0.93 +/- 0.02) and the critical density p(c) scales as p(
c) x (d/W)(1.16 +/- 0.02), where d is the width of the bottleneck and W is
the width of channel. The plot of the rescaled Row rate against the rescale
d density collapses onto a single curve. (C) 2001 Elsevier Science B.V. All
rights reserved.