Latent Heat of a Traffic Model

We have studied the optimal velocity model (Bando et al., Jpn J Indust Appl Math 11:203, 1994; Phys Rev E 51:1035, 1995; J Phys I Fr 5:1389, 1995) for highway traffic. On a microscopic level, traffic flow is described by Bando’s optimal velocity model in terms of accelerating and decelerating forces. We define an intrinsic energy of the model. We find a latent heat when the system undergoes a phase transition from single phase traffic (free flow) to a phase that contains two different, a dense and a dilute phase (congested or stop–and–go flow). Here we report on properties of the latent heat.