Do I need to install anything?

No. It runs in any modern browser, free, with no account required.

For First Responders · Traffic Flow

Traffic Flow for a sandpile avalanche

Built for first responders planning or training for real incidents. Run fast what-if scenarios for response planning and training — no software to install in the field. Simulate a sandpile avalanche live below — adjust the inputs and watch it respond, right in your browser.

Traffic Flow StudioLive

Nagel–Schreckenberg model · phantom jams

Controls

Speed1×

A ring road of cars. Random braking alone creates “phantom” traffic jams that travel backward — no accident needed.

Presets

Density

Random braking

▶ Run in Python

Data Inspector

Cells160

Avg speed0.00

Density0.30

ModelNagel–Schreckenberg

Governing equation

q = ρ v = 0.30 \times 0.00 = 0.000

Reading this result: Above critical density: stop-and-go waves dominate. Average speed drops sharply — this is the falling branch of the fundamental diagram.

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Frequently asked questions

Is this good for first responders?: Yes — this version of "Traffic Flow for a sandpile avalanche" is framed for first responders planning or training for real incidents. Run fast what-if scenarios for response planning and training — no software to install in the field.
Do I need to install anything?: No. It runs in any modern browser, free, with no account required.