Pressure in Tank: Increasing or Decreasing?

[Idea04]

If you have pressured water being forced out the bottom of a tank. And pressured water is entering through another point at the bottom of the tank. Would the difference in pressure add to the total pressure in the tank? So if you have 20 psi entering the tank and 15 psi pressure in the tank would you have the difference of 5 psi pressure added to the tank pressure?

 

[andrevdh]

If the tank you are referring to is closed then the entry pressure will be transmitted to the fluid in it and the fluid in the tank will end up at the same pressure of 20 psi. This is like pressurising a bottle of gas with a pipe from a compressor. The pressure is communicated to all of the gas in it, bringing all of the gas to the same pressure. This is true if the source can maintain the pressure while pressurising the contents. I do not know how valves effect the situation. What I would think would happen if there are valves in the in- and outlets is that the pressures will be maintained and not communicated, that is the valves bleed the fluid into a region with a different pressure.

 

[kyle8921]

The pressure in a tank is determined by the amount of force exerted on the walls of the tank by the molecules of the fluid inside. In this scenario, the pressure in the tank would depend on the rate at which water is entering and exiting the tank. If the rate of water entering the tank is greater than the rate of water exiting, the pressure in the tank would increase. Conversely, if the rate of water exiting the tank is greater than the rate of water entering, the pressure in the tank would decrease.

In this case, if 20 psi of water is entering the tank and 15 psi of water is exiting, the net pressure in the tank would be 5 psi. This is because the pressure exerted by the water entering would be added to the pressure exerted by the water already in the tank. However, if the rate of water exiting the tank increases and becomes greater than the rate of water entering, the pressure in the tank would decrease.

Overall, the pressure in the tank would be determined by the balance between the rates of water entering and exiting, and the difference in pressure between the two points would contribute to the overall pressure in the tank.