05 August 2009

Traffic Wave Simulation

Have you ever wondered why traffic comes to a standstill when there is an accident in the other carriageway of the freeway? Here's a simulation to explain it. Traffic Wave Simulation - screamyGuy:
The fact that the wave propagates explains why the source of the traffic jam is often not near where the traffic will clear up. By increasing the density of the incoming traffic, you can also see how intolerant of minor disturbances a heavy flow can be. Increase the traffic rate and note that halting as little as two cars can cause a jam that fills the entire screen! This implies that the hour you spent in traffic this morning may be little more than the remnants of a near collision when someone was messing with their stereo.

Those things are so frequent on the N1 between Pretoria and Johannesburg that I try to avoid travelling to Johannesburg unless it's absolutely necessary.
For more detailed explanations, see here http://trafficwaves.org/.


James Higham said...

Very interesting theory, that.

Tauratinzwe said...

One study showed that traffic clustering on expressways fits classic standing wave theory in physics. Your article quoted would fit in those calculations, I think.

bigbluemeanie said...

Very interesting. Over here we have the M25 orbital, which is susceptible to these dynamics. They installed variable speed limits to try and control the "Mexican waves" which result from earlier accidents. I'm not convinced the overhead controls work.


Related Posts with Thumbnails