Nonlocal Generalized Aw-Rascle-Zhang model: well-posedness and singular limit
Elio Marconi, Laura V. Spinolo
TL;DR
This work analyzes a nonlocal two-equation GARZ-type traffic model where the flux depends on a nonlocal density proxy $\xi$ computed with an anisotropic kernel. It first proves well-posedness (existence, uniqueness, stability) of the nonlocal Cauchy problem and derives key a priori bounds, including $0\le \xi\le 1$ and $0\le \rho\le \frac{1}{1- tC(V)\|z_0\|_{L^{\infty}}}$, with propagation of regularity. It then establishes a nonlocal-to-local limit for exponential kernels, showing that as the kernel concentrates to a Dirac delta the nonlocal system converges to the local GARZ model, with a novel Oleinik-type estimate playing a central role. The results include a global-in-time existence under additional structural assumptions and a stability framework with respect to initial data, marking the first rigorous limit for a coupled system of two non-decoupled equations with a nonlocal flux. Overall, the paper provides a comprehensive, mathematically rigorous foundation for nonlocal traffic models and their local limits, with implications for modeling and analysis of vehicular flows.
Abstract
We discuss a nonlocal version of the Generalized Aw-Rascle-Zhang model, a second-order vehicular traffic model where the empty road velocity is a Lagrangian marker governed by a transport equation. The evolution of the car density is described by a continuity equation where the drivers' velocity depends on both the empty road velocity and the convolution of the car density with an anisotropic kernel. We establish existence and uniqueness results. When the convolution kernel is replaced by a Dirac Delta, the nonlocal model formally boils down to the classical (local) Generalized Aw-Rascle-Zhang model, which consists of a conservation law coupled with a transport equation. In the case of exponential kernels, we establish convergence in the nonlocal-to-local limit by proving an Oleinik-type estimate for the convolution term. To the best of our knowledge, this is the first nonlocal-to-local limit result for a system of two non-decoupling equations with a nonlocal flux function.
