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zax
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Hey, I have a problem in which there are two water tanks with different pressure. If they are connected together, how to calculate the time it takes to arrive to the steady state(same pressure)?
Thank you.
Thank you.
Q_Goest said:hi zax,
The flow of water is restricted by the various pipe lengths, fittings and valves you have installed between the tanks. The change in pressure is also a function of the thermodynamics of the air in the tank and heat transfer.
Look through this post here to get a general idea of some of the concepts and what you might do to calculate things. In your case you might want to simplify the heat transfer and thermodynamics a bit. If you need help understanding flow restrictions, check the attached. Generally in industry, we use the Darcey Weisbach equation as indicated on the attached.
All you should need to do is to ensure the irreversible pressure drop in the pipe from each tank to the point where the two lines connect is relatively small. The best way to do this is to use lines large enough so that given your highest expected flow through those pipes, the flow restriction is small. In the case of a 30 psi head tank, you might for example try to minimize the irreversible pressure drop between the tank and T to a few psi or less. The smaller you make this pressure loss, the closer the tanks will come to emptying equally.tletterm said:What if there was no heat transfer just 2 cold water tanks at atmospheric pressure and both tanks were say a head pressure of 30psi? What would be the best claculation method to ensure both tanks draw water at the same time and not have one tank draw down before the other one starts its draw down?
Not sure what you mean by the "cross sectional venting". Are your tanks enclosed such that they need a vent? Or are you referring to the liquid discharge lines? In any case, I'd suggest performing a flow analysis on every line so there are no surprises.tletterm said:Does the cross sectional venting associated with the Tank have to be at least 1-1/2 the cross sectional diameter of the discharge piping configeration in order to flow correctly should this be calculated as well or does it matter.
I would always do a flow analysis including any acceleration losses to ensure adequate NPSH to the pump. Basically, add the irreversible flow losses into the equation for head and acceleration losses as shown by equation 16 of the manual I posted above.tletterm said:One more thing if a pump is attached to this configeration does accelerated suction velocities need to be accounted for to ensure the ballanced pressure at the connection point of the lines connecting the two tanks?
Q_Goest said:Not sure what you mean by the "cross sectional venting". Are your tanks enclosed such that they need a vent? Or are you referring to the liquid discharge lines? In any case, I'd suggest performing a flow analysis on every line so there are no surprises.
I would always do a flow analysis including any acceleration losses to ensure adequate NPSH to the pump. Basically, add the irreversible flow losses into the equation for head and acceleration losses as shown by equation 16 of the manual I posted above.
To connect two tanks together, you will need to use a pipe or hose to create a physical connection between the two tanks. The pipe or hose should be securely attached to the outlet valve of one tank and the inlet valve of the other tank.
You will need a pipe or hose, as well as connectors and clamps to secure the pipe or hose to the tanks. You may also need a wrench or pliers to tighten the connectors and clamps.
Yes, you can connect tanks of different sizes together as long as you have the appropriate connectors and fittings to create a secure connection. It is important to ensure that the tanks are compatible and the larger tank does not overpower the smaller tank.
Connecting two tanks together can increase the total volume of liquid or gas contained in the tanks. This can be useful for applications that require a larger quantity of the substance, or for providing a backup supply in case one tank runs out.
Yes, it is important to follow proper safety procedures when connecting tanks together. Make sure the tanks are clean and free of any debris or contaminants. Also, ensure that the tanks are securely anchored and there are no leaks in the connection. It is also important to follow any specific safety guidelines provided by the manufacturer of the tanks.