Qualitative advice on two phase flow problem.

[SteveNgabo]

Hi guys I have a rather qualitative question. let's imagine a tank with two openings. pressure is measured at one opening (A) to be at a constant 33 bar at time t=0s. the other opening(B) is at atmospheric pressure.
Inside the tank we have a two phase flow half is N₂ gas and the other half is H₂O₂(hydrogen peroxide in liquid form) the tank itself is made out of aluminium for weight saving purposes and it's not very big about the size of a paintball tank.
The question here is if we closed opening A with a valve (solenoid) so that pressure at A becomes 0, how fast would the pressure decrease. I know this is not an easy question because it is time dependent. I had to try and simulate this on solidworks but two-phase flow is not available. So before trying it with Comsol I would like to know maybe from someone's experience if it will be fast pressure drop(<5sec) or a slow one(>10sec)

 

[rollingstein]

Fast I think.

With a pressure drop as big as that, the flow velocity would be sonic (i.e. choked flow) I assume?

Your description sounds less tank and more a nozzle or a pipe.

 

[SteveNgabo]

the B opening leads to a nozzle indeed. Thanks for your insight