Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Traffic flow

  1. Jun 8, 2007 #1


    User Avatar
    Gold Member

    Has any one seen a traffic flow simulator, or used a program similar to this?

    I would like to simulate the effects of slowing traffic speed limit in a major city, and see what effect it would have on the motorways, maybe the software is all ready in use some where?
  2. jcsd
  3. Jun 10, 2007 #2


    User Avatar
    Homework Helper

    In general, a slower speed limit will result in higher traffic. This is because the number of cars passing by any specific cross section of a street / highway is reduced with a slower speed limit (or larger gaps time wise).

    In theory, even if all drivers maintain a 2 second following distance, the flow with a faster speed limit is increased slightly by the reduced time it takes for a car to pass across a cross section of a street.

    In practice, a higher speed limit allows for cars to compensate more for the normal impedances to traffic flow, like lane changes or cars merging into traffic from side streets.

    The best way to improve traffic flow is to synchronize the street signals. Do a web search for "traffic signal synchronization algorithm", and you'll find a lot of hits, probably including some simulations. It's easier to synchronize signals if all streets are one way.
  4. Jun 10, 2007 #3
    There's a simple first order hyperbolic partial differential equation which can model traffic flow. You can derive it from conservation of cars. Search for 'traffic flow pde' or something like that.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook