Particle Hopping vs . Fluid - Dynamical Models for Traffic Flow

Energy. The Los Alamos National Laboratory strongly supports academic freedom and a researcher's right to publish; as an institution, however, the Laboratory does not endorse this viewpoint of a publication or guarantee its technical correctness. Although particle hopping models have been introduced into traac science in the 1950s, their systematic use has only started recently. Two reasons for this are, that they are advantageous on modern computers, and that recent theoretical developments allow analytical understanding of their properties and therefore more conndence for their use. In principle, particle hopping models t between microscopic models for driving and uid-dynamical models for traac ow. In this sense, they also help closing the conceptual gap between these two. This paper shows connections between particle hopping models and traac ow theory. It shows that the hydrodynamical limits of certain particle hopping models correspond to the Lighthill-Whitham theory for traac ow, and that only slightly more complex particle hopping models produce already the correct traac jam dynamics, consistent with recent uid-dynamical models for traac ow. By doing so, this paper establishes that, on the macroscopic level, particle hopping models are at least as good as uid-dynamical models. Yet, particle hopping models have at least two advantages over uid-dynamical models: they straightforwardly allow microscopic simulations, and they include stochasticity.