2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/111806Traffic congestion is usually observed at the upper streams of bottlenecks such as tunnels. Congestion appears as stop-and-go waves and high density uniform flow. We perform simulations of traffic flow with a bottleneck using the coupled map optimal velocity model. The bottleneck is expressed as a road segment with speed reduction. The speed reduction in the bottleneck controls the emergence of stop-and-go waves. A phenomenological theory of bottleneck effects is constructed.11pages; Small changes were made/ This paper was accepted by J. Phys. Soc. JpnPhysics and SocietyStatistical Mechanicstext