Traffic waves
Stories from Physics
for 11-14
14-16
Researchers have modelled flowing traffic as analogous to a fluid and have applied wave equations to predict the behaviour of cars in heavy traffic. The wave-equation models suggest that jams can occur spontaneously in homogeneous traffic flow, if the density of vehicles exceeds a particular value. Traffic can be modelled as existing in a number of states, for example free flowing and traffic jams, with phase transitions occurring between the states.
References
M. J. Lighthill, G. B. Whitham, On kinematic waves: II. A theory of traffic flow on long crowded roads, The Royal Society: Proceedings A, vol. 229, no. 1178, 1995, pp. 317-345.
B. S. Kerner, & P. Konhäuser, P. (1993). Cluster effect in initially homogeneous traffic flow. Physical Review E, vol. 48, no. 4, 1993, pp. 2335-2338.
B. S. Kerner, & H. Rehborn, Experimental properties of phase transitions in traffic flow. Physical Review Letters, vol. 79, no. 20, 1997, 4030.