Time taken for pressure equalization between two tanks

In summary: P1(t)=P2(t)+v(t)*P1*L*P2/AP1*L*P2/A=0In summary, pressure equalization between two tanks can be achieved by using equations Ptot = (P1V1+P2V2)/Vtot. The exponential constant B is assumed to be the same for the tanks. The equations can be used to calculate how the pressure differences result in acceleration of air into, through and out of the pipe, and for how the rate of flow affects P1 and P2.
  • #1
Raghav Seetharamu
3
0

Homework Statement


How to calculate time taken (rough approximation) for pressure equalization between two tanks.
Both the tanks have same fluid (Air).

Homework Equations


Rough equilibrium pressure can be achieved by using equations Ptot = (P1V1+P2V2)/Vtot.
Thought of using exponential equation P=Ae^(Bt) for calculating time required for pressure equalization.
A and B are constants.
P=A1e^(-Bt) for tank with decreasing pressure;
P=A2e^(Bt) for tank with increasing pressure;

Exponential constant B, is assumed to be same for the tanks. Am I correct with this assumption?

The Attempt at a Solution


P1 = 1000mbar; P2 = 0.1mbar, V1=6m3, V2 = 1m3,
Ptot = 860 mbar

P=1000*e^(-Bt) for tank with decreasing pressure ;
P=0.1*e^(Bt) for tank with increasing pressure;

How to obtain the exponential constant and hence the time taken for pressure equalization using these equations?
 
Physics news on Phys.org
  • #2
Hello Rahghav, ##\qquad##:welcome: ##\qquad## !

To settle this somewhat, you need more information: a certain amount of material has to be transported from one vessel to the other. The rate depends on the pressure difference and on the resistance in that transport: is it a thin and very long tube or a big short pipe ?
 
  • #3
BvU said:
Hello Rahghav, ##\qquad##:welcome: ##\qquad## !

To settle this somewhat, you need more information: a certain amount of material has to be transported from one vessel to the other. The rate depends on the pressure difference and on the resistance in that transport: is it a thin and very long tube or a big short pipe ?
Thanks for reverting:)
They are connected through relatively big and short pipes.
 
  • #4
Suppose the pressures at time t are P1(t), Ppipe(t), P2(t). A= cross-sectional area of pipe, L=length.
Mass velocity in pipe = v(t).
Can you write some equations for how the pressure differences result in acceleration of air into, through and out of the pipe, and for how the rate of flow affects P1 and P2?
Bear in mind that density depends on pressure. You should probably assume adiabatic compression/decompression.
 

FAQ: Time taken for pressure equalization between two tanks

What is the equation for calculating the time taken for pressure equalization between two tanks?

The equation for calculating the time taken for pressure equalization between two tanks is:
t = (V1 - V2) * (P1 - P2) / F
where t is the time in seconds, V1 and V2 are the volumes of the two tanks in cubic meters, P1 and P2 are the pressures in pascals, and F is the flow rate in cubic meters per second.

How does the volume of the tanks affect the time taken for pressure equalization?

The volume of the tanks directly affects the time taken for pressure equalization. The larger the volume of the tanks, the longer it will take for the pressures to equalize. This is because there is more space for the gas molecules to spread out and equalize the pressure.

What is the significance of the pressure difference in the equation?

The pressure difference (P1 - P2) in the equation represents the driving force for the pressure equalization process. The greater the pressure difference, the faster the equalization process will be.

Does the flow rate have any impact on the time taken for pressure equalization?

Yes, the flow rate has a direct impact on the time taken for pressure equalization. The higher the flow rate, the faster the gas molecules will move between the two tanks, resulting in a shorter time for pressure equalization.

Are there any other factors that can affect the time taken for pressure equalization between two tanks?

Other factors that can affect the time taken for pressure equalization include temperature, type of gas, and the presence of any barriers or obstructions between the two tanks. These factors can impact the speed at which gas molecules move and therefore affect the overall time for pressure equalization.

Similar threads

Back
Top