Macroscopic flow characterization at T-junctions

Abstract

At T-junctions, a minor road meets a main road and merging vehicles from the minor road create traffic bottlenecks as significant interactions between vehicles occur. These interactions reduce road capacity resulting in congestion. The Lighthill-Whitham-Richards (LWR) model is widely employed to characterize traffic flow. However, this model only considers small changes in flow which can be inadequate for T-junctions. Thus, a new model is proposed which is based on driver response during transitions at these junctions. The proposed and LWR models are evaluated using the first order upwind scheme (FOUS). The Courant-Friedrich-Lewy (CFL) condition is employed to ensure model stability. Results are presented which show that the proposed model better characterizes traffic flow at T-junctions.

Keywords

• Lighthill-Whitham-Richards model
• First order upwind scheme
• CFL condition
• Driver response
• Junctions