It all started with the computer programm NUMSTA ^(R) developed for the Swissmetro project (similar to what is now Hyperloop). It allows to simulate the wave propagation in road and rail tunnels and thus to obtain the time dependent flow values in such systems.

The simulation programm has been developed continously.

Now, it can be used to answer very specific questions about the flow propagation in complex tunnel systems including compressible effects, thermal effects, vehicles and fans.