Pedestrian flow through multiple bottlenecks

TL;DR

This paper models pedestrian evacuation through multiple bottlenecks using the floor field model, revealing phase transitions, metastable states, and the complex effects of local improvements on overall evacuation efficiency.

Contribution

It introduces a theoretical framework for understanding pedestrian flow dynamics with multiple bottlenecks and analyzes the impact of local versus global optimization strategies.

Findings

Large inflow causes congestion and metastable states.

Phase transition from free flow to congestion is characterized.

Local improvements can negatively affect total evacuation time.

Abstract

We investigate the dynamics of the evacuation process with multiple bottlenecks using the floor field model. To deal with this problem, we first focus on a part of the system and report its microscopic behavior. The system is controlled by parameters of inflow and the competitiveness of the pedestrians, and large inflow leads to a congested situation. Through simulations, the metastable state induced by conflicts of pedestrians is observed. The metastability is related to the phase transition from free flow to congestion. The critical condition of the transition is theoretically derived. In addition, we give simulation results of situations with multiple bottlenecks. They imply that local improvement of pedestrian flow sometimes adversely affects the total evacuation time, and that the total optimization of the system is not straightforward.