Low pressure, high velocity flow vs static pressure

[T C]

TL;DR

I want to discuss an imaginary scenario here where we have a compressible flow flowing through a tube at 0.99 barA pressure and at 300 m/s velocity and that flow is released into 1 barA pressure. Is it possible or not.

In this scenario, we have a compressible flow at 0.99 barA pressure and flowing at 300 m/s velocity and is released into 1 barA pressure. Point is, whether the flow can be released at 1 barA or not at the release pressure is higher than the pressure of the compressible fluid inside the tube. And here is my thought in this regards. The static pressure of the flow may be lower than the release pressure, but it has another pressure and that's the dynamic pressure. At 300 m/s velocity, the dynamic pressure is around 0.7 barA and when that's added to the existing static pressure of the compressible fluid, the total pressure far exceeds the release pressure and the flow can be easily released. For the sake of simplicity, it has been assumed that the tube is frictionless and the static fluid at 1 barA pressure, where this flow is released, is the same and density difference is negligible.
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[Lnewqban]

How are you measuring each of those pressures?

 

[Chestermiller]

Is this supposed to be a steady state flow? How was the flow at the lower pressure established on the upstream side?

 

[Dullard]

I don't see how your situation can exist unless there is a divergent nozzle at the tube exit.

 

[T C]

How are you measuring each of those pressures?

Static pressures are chosen and dynamic velocity calculators available on net. Let's consider the both the fluids at standard temperature. The density can be calculated easily and just put those values into the calculator and you can get the results.

Is this supposed to be a steady state flow? How was the flow at the lower pressure established on the upstream side?

Can't understand what you want to mean.

I don't see how your situation can exist unless there is a divergent nozzle at the tube exit.

Why a divergent section would be necessary?

 

[T C]

In case of De Laval nozzle, the release pressure (mentioned as ambient pressure in the page) can be 2-3 times higher than the pressure at the exit of the nozzle. If that's true, that simply means a high velocity flow of lower pressure can easily enter at higher pressure if the gross i.e. total sum of static and dynamic is higher than the release pressure.