Introduction of frictional and turning function for pedestrian outflow with an obstacle

Abstract

In this paper, two important factors which affect the pedestrian outflow at a bottleneck significantly are studied in detail to analyze the effect of an obstacle setup in front of an exit. One is a conflict at an exit when pedestrians evacuate from a room. We use floor field model for simulating such behavior, which is a well-studied pedestrian model using cellular automata. The conflicts have been taken into account by the friction parameter. However, the friction parameter so far is a constant and does not depend on the number of the pedestrians conflicting at the same time. Thus, we have improved the friction parameter by the frictional function, which is a function of the number of the pedestrians involved in the conflict. Second, we have presented the cost of turning of pedestrians at the exit. Since pedestrians have inertia, their walking speeds decrease when they turn and the pedestrian outflow decreases. The validity of the extended model, which includes the frictional function and the turning function, is supported by the comparison of a mean-field theory and real experiments. We have observed that the pedestrian flow increases when we put an obstacle in front of an exit in our real experiments. The analytical results clearly explains the mechanism of the effect of the obstacle, i.e., the obstacle blocks pedestrians moving to the exit and decreases the average number of pedestrians involved in the conflict. We have also found that an obstacle works more effectively when we shift it from the center since pedestrians go through the exit with less turning.

Statistical properties of gravity-driven granular discharge flow under the influence of an obstacle

“…The clogging probability can be reduced when an obstacle is placed just above the orifice [5,6]. Similar effect can also be observed in various other phenomena relating to bottleneck clogging [6][7][8]. According to Ref.…”

Role of driving force on the clogging of inert particles in a bottleneck

“…A practical solution which seems to release such pressure is the placement of an obstacle just in front of the outlet. Indeed, this strategy has been proved to be efficient in clogging prevention for both silos [8] and room evacuation [5,[10][11][12].…”

Silo Clogging Reduction by the Presence of an Obstacle

“…A practical solution that is commonly implemented to improve the flow in both scenarios, people escaping from a room and the discharge of a silo, is the placement of an obstacle (or insert) just before (or above) the exit [2,[12][13][14][15][16][17][18]. In the case of the silo discharge, selecting the right insert position and size has been proved to increase the flow rate up to 10% [17,18].…”