Observation on limited access facilities suggests that up to a maximum flow, speed does not decline while density increases.
The mass contracts, and its density increases.
At the same time, it is easy to see that the specific volume decreases or similarly the density increases.
As the fluid flow crosses the shock wave, its speed is reduced and temperature, pressure, and density increase.
However, some of the density increase is compression under the enormous pressures inside the Earth.
If the chamber is made smaller without allowing gas in or out, the density increases and the specific volume decreases.
But even with the density increase, developers said they were having trouble coming up with financially feasible projects under the city's growth restrictions.
For 2D patterns the density increase is very dependent on the nature of the pattern.
The first has the advantage of producing particularly strong contrast, but at the cost of a sometimes inconveniently large density increase.
The resistance in flashtubes is not constant, but quickly drops as current density increases.