🛣️ Highway On-Ramp Bottleneck: Fundamental Diagram, Shockwave and Ramp Metering (2D)

Top view of a five-kilometre motorway with an on-ramp, simulated with a cell transmission model, with road colour showing speed and a red bar marking the tail of the queue. Set the mainline and ramp demand, the metering limit, lanes, free-flow speed, wave speed and jam density, and see the capacity, the queue growing backwards at the shock wave speed and how metering keeps the mainline flowing. The fundamental diagram, vehicle conservation, shock speed and discharge are checked numerically, with four in-page numerical checks.