01628776

Component

Large-scale network modeling using the Macroscopic Fundamental Diagram (MFD) is widely based on the single-reservoir model, where the variation of the accumulation of circulating vehicles in the reservoir equals inflow minus outflow. This simple accumulation-based model suffers from the infinite-wave speed dropback, which is problematic when the inflow varies rapidly. To overcome this limitation, a trip-based model has been recently proposed, but whose solution cannot be obtained analytically. In this paper the authors compare both models under piecewise linear MFD and a piecewise constant demand. These assumptions allows to establish the exact solution of the accumulation-based model, and approximate solutions of the trip-based model at any order using Taylor series. More-over a very flexible event-based simulation framework is implemented to solve the latter model, making it a promising tool to account for heterogeneity among travel distances. Thanks to these resolution schemes our comparisons highlight the inaccuracy of the accumulation-based approach in transient phase when the demand varies rapidly.

This paper was sponsored by TRB committee AHB45 Standing Committee on Traffic Flow Theory and Characteristics.

01618707

17-04928

English

21p

2017

Transportation Research Board 96th Annual Meeting

Digital/other

Figures; References

Macroscopic traffic flow; Networks; Numerical analysis; Simulation; Trip length; Urban areas

Highways; Planning and Forecasting

Transportation Research Board Annual Meeting 2017 Paper #17-04928

TRIS, TRB, ATRI

Dec 8 2016 11:53AM