Dynamic pressure variances in sealed and pressurised systems

AI Thread Summary
The discussion centers on the behavior of pressurized fluids in a sealed system with a central agitator and attached cylinders. The user inquires about the potential for a Venturi effect to draw liquid back into the cylinder when the agitator is in motion, while also noting that the system's design limits the creation of voids. Concerns are raised about the risk of increased temperature and pressure in a closed system, which could lead to destructive failures if the liquid boils. The user also speculates on the possibility of creating a pressure gradient and oscillations for underwater communication. Overall, the conversation highlights the complexities of fluid dynamics in pressurized systems and the potential implications for system design and safety.
Roger1946
Hi
Last did physics about 50 years ago but have become interested in how pressuried fluids behave in sealed containers when they are rapidly agitted or otherwise brought into motion.

Envisage a large circular container with a central power driven agitator. Two cylinders are attached . The whole system is pressurised with the liquid static. The agitator is now powered up and the liquid in the circular cyclinder is provided a dynamic force in one direction as well as being under pressure.
Each cylinder is controlled by two separate flaps, one to allow the circulating pressurised liquid to enter the cylinder (this opens into the flow of the liquid) and the other opens against the flow to permit the liquid in the cycliner to exit.

The question I have is to what extent will the rotating pressurise fluid create a venturi and suck the liquid back out of the cylinder.
Or could anyone suggest any literature I should read?
 
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You might get some recirculation flow but since the system is full of liquid you won't be able create a void anywhere because any liquid removed would have nowhere to go .

The usual result of having an agitator of any type in a totally closed system without an adequate flow circulation path or means of removing heat is that the whole system just gets hotter and hotter and the pressure rises until something breaks .

If the heating is enough to make the liquid boil then the results at final failure can be very destructive .
 
Thanks for your thoughts Nidum.
I had hoped that the circular flow would induce a pressure gradient rising from P1 at the centre of the agitator to a greater pressure at the container wall P2. Also when the flow was deflected inwards by the outgoing cylinder flap the disorganised flow area after the edge of the flap would be at a pressure (P0) lower than P1 or P2 . This isolated lower pressure area could be turned on or off by the rapid opening/closing of the flap. All of this would help the volume of the cylinder to oscillate setting up a pressure vibration that could be used as an audio source at the end of the cylinder as a means of communication underwater.

Perhaps my variant of a water hammer as a communication device has become too commplicated!

Thanks Roger1946
 
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