Daisy Chaining Kegs

[Zwickel]

Jay, I cannot resist, sorry mate....



:lol: :wub:

 

[kenlock]

I didn't know Zwickel was David Boon! ???

 

[jayandcath]

I didn't know Zwickel was David Boon! ???

One and the same, Twins separated at birth.

Jay

 

[Spartan 117]

I didn't know Zwickel was David Boon! ???

HAHAHAHAHAHAHAHAHAHAHAHAHAHA!!!!!!!!!

Aaron

 

[frogman]

Banking dose work with home brew kegs I know because I have done it.

Cheers Damien.

 

[Zwickel]

yes, thats my brother, for some reason hed to change hes name when he emigrated to Tasmania


sorry Jay, I didnt want to hijack your thread, but I think all questions are answered.

Cheers :icon_cheers:

 

[Offline]

A friend of mine told me the club he used to work at here uses this method of dispensing kegs, he called it piggie backing. He also told me that if they had a slow selling beer they would stick it on the end of a line (not of the same brand) and allow it to mix with the higher turnover beer. :icon_vomit:



:icon_offtopic:

Nah it would be the sum of the three preassures(or close to there is an equation but i never paid attention to physical chemistry ). Three joining flows into one area of lesser area will increase preassure always, its just like when two rivers meet the current generally increases.

Aaron

This statement is not even close to being correct. Flow and pressure are different (but related) things, first of all flow will only occur if there is a pressure differential and the direction of flow will be from high to low pressure. Now if your analogy was correct then there would be 3 times greater the pressure in the beer line than in the kegs. That would mean beer would flow in to the kegs not out of them? Even if the kegs were set up in the way you read the OP the maximum pressure in the system would be that supplied by the regulator and this would only be when the beer tap is shut, ie no flow.

you would have 3 times the flow not pressure

 

[Spartan 117]

A friend of mine told me the club he used to work at here uses this method of dispensing kegs, he called it piggie backing. He also told me that if they had a slow selling beer they would stick it on the end of a line (not of the same brand) and allow it to mix with the higher turnover beer. :icon_vomit:



:icon_offtopic:



This statement is not even close to being correct. Flow and pressure are different (but related) things, first of all flow will only occur if there is a pressure differential and the direction of flow will be from high to low pressure. Now if your analogy was correct then there would be 3 times greater the pressure in the beer line than in the kegs. That would mean beer would flow in to the kegs not out of them? Even if the kegs were set up in the way you read the OP the maximum pressure in the system would be that supplied by the regulator and this would only be when the beer tap is shut, ie no flow.

you would have 3 times the flow not pressure

Firstly I think it's close to being correct, and if you want to produce some math or other evidence that implies the contrary then be my guest and I'll be the first to admit I'm wrong.

1) "Flow and pressure are different (but related) things, first of all flow will only occur if there is a pressure differential and the direction of flow will be from high to low pressure. Now if your analogy was correct then there would be 3 times greater the pressure in the beer line than in the kegs. That would mean beer would flow in to the kegs not out of them?"

Ok this statement I think you got confused with... I'm not sure just my opinion. What i was saying is that when the 3 or however many lines come together they will all have there own independent pressure with respect to the volume the fluid occupies, when you have an initial pressure joining another independent pressure unless the volume of area with which they enter is proportional to the volume of the area they left there will be a pressure increase

This is in accordance with Boyle's Law where P1V1=P2V2 (P and V are Pressure and Volume)

2)"That would mean beer would flow in to the kegs not out of them?"

NO!!! It does not mean that. A kegging system is one of isolation (known as an isobaric system) where if there is no volume change pressure is constant (and as a result so are other factors that contribute to the thermodynamic stability of a system such as work and internal energy) however when the volume changes, such as adding a line for the beer to come out of you immediately incorporate a new amount volume which is at atmospheric pressure, the fluid of the system (beer) will rush to fill this area to obtain a state of equilibrium and if the line and its connections aren't strong enough to hold that pressure the lines may break as you must do work if there is a volume change in a isobaric system.

Consistent with teh 1st law of thermodynamics dU= dq-dw (states that a change in wrok(w) will results in a change in internal energy (dU). dq is the heat added or removed from a system)



Cheers

Aaron

 

[Zwickel]

no matter how many kegs youre connecting together, could be endless, the resulting pressure will be the arithmetic middlepressure of all.
That means, the pressure will equalizes to the middle value.

For example, if you connect two kegs, one at 100 KPa and the other one at 1.2 KPa, the resulting pressure will be 1.1 KPa.....as long as the kegs are of the same volumes.

Cheers

 

[Spartan 117]

no matter how many kegs youre connecting together, could be endless, the resulting pressure will be the arithmetic middlepressure of all.
That means, the pressure will equalizes to the middle value.

For example, if you connect two kegs, one at 100 KPa and the other one at 1.2 KPa, the resulting pressure will be 1.1 KPa.....as long as the kegs are of the same volums.

Cheers

This would be true if refrenced to "daisy chaining" of kegs however we're talking about convergence of systems not one giant system and the value wouldn't be 1.1kpa more like the mean of the 2 which is 55.1kpa.

cheers

Aaron

Aaron

 

[Zwickel]

Aaron, it doesnt matter if you are daisy chaining the kegs or just connect altogether to a manifold, youll always get the arithmetic middlepressure.

This would be true if refrenced to "daisy chaining" of kegs however we're talking about convergence of systems not one giant system and the value wouldn't be 1.1kpa more like the mean of the 2 which is 55.1kpa.

sorry mate, thats simply wrong

Cheers :icon_cheers:

 

[Offline]

Firstly I think it's close to being correct, and if you want to produce some math or other evidence that implies the contrary then be my guest and I'll be the first to admit I'm wrong.

1) "Flow and pressure are different (but related) things, first of all flow will only occur if there is a pressure differential and the direction of flow will be from high to low pressure. Now if your analogy was correct then there would be 3 times greater the pressure in the beer line than in the kegs. That would mean beer would flow in to the kegs not out of them?"

Ok this statement I think you got confused with... I'm not sure just my opinion. What i was saying is that when the 3 or however many lines come together they will all have there own independent pressure with respect to the volume the fluid occupies, when you have an initial pressure joining another independent pressure unless the volume of area with which they enter is proportional to the volume of the area they left there will be a pressure increase

This is in accordance with Boyle's Law where P1V1=P2V2 (P and V are Pressure and Volume)

Boyles law is for an ideal gas, not an incompressible liquid (beer) so first of all it is completely irrelevant. But even if you wanted to consider beer as an ideal gas you would find that Boyles law will tell you that your pressure will drop (to atmospheric pressure actually) because volume one is the keg and volume two would be well the atmosphere. But because beer is, for all intents and purposes, an incompressible liquid there is no volume change, it just moves.

2)"That would mean beer would flow in to the kegs not out of them?"

NO!!! It does not mean that. A kegging system is one of isolation (known as an isobaric system) where if there is no volume change pressure is constant (and as a result so are other factors that contribute to the thermodynamic stability of a system such as work and internal energy) however when the volume changes, such as adding a line for the beer to come out of you immediately incorporate a new amount volume which is at atmospheric pressure, the fluid of the system (beer) will rush to fill this area to obtain a state of equilibrium and if the line and its connections aren't strong enough to hold that pressure the lines may break as you must do work if there is a volume change in a isobaric system.

Consistent with teh 1st law of thermodynamics dU= dq-dw (states that a change in wrok(w) will results in a change in internal energy (dU). dq is the heat added or removed from a system)



Cheers

Aaron

When the tap is open you have atmospheric pressure at the tap and your keg pressure in the keg and some sort of gradient between the two whose profile is dependent on the size and type of restriction between the two. But at no point will the pressure be higher then in the keg, which is what you initially stated. So if the beer line can handle the closed tap pressure it will be fine. Im assuming that he will be using the same pressure, beer tap and line as his current system. I know this is off topic as we are not talking about the same set up as the OP but the pressure will be virtually the same no mater which way you set it up is my point.

 

[Bribie G]

It was the default back in the seventies when there were only two beers on tap in Qld, XXXX and Carlton so they could chain up a few days supply in one hit. Rumour had it that at least one of the kegs would contain cold water. Urban myth ? :huh:

 

[Zwickel]

For example, if you connect two kegs, one at 100 KPa and the other one at 1.2 KPa, the resulting pressure will be 1.1 KPa.....as long as the kegs are of the same volumes.

oh man....I have to apologize, I confused KPa with bar, it should be one at 100KPa and the other one at 120KPa, resulting 110KPa middlepressure

 

[Pollux]

This is how most pubs run their house beers.
I have seen 14 kegs daisied up before, it's quite a site.

 

[LethalCorpse]

Back in the box spartan, you're talking rubbish.

If the tap is shut, there's no flow. Since there's no flow there must be no pressure differential. The pressure throughout the entire system is the same as it is at the regulator. Whether you've got three kegs hooked up in parallel or in series, this is the case. The only variation in pressure is with depth - the bottom of the keg will be at a higher pressure than the top of the keg. And that's true at all points in the system, if you take a bit of the beer line and raise and lower it, the pressure in the bit of line that you're holding will always be at the same pressure as the beer in the keg at that same height.

When you open the tap, the restriction of the plumbing comes into play. With the kegs in parallel, the flow rate will be higher - three short thin pipes joined at either end is the same as one short fat pipe. When they're in series, it will be lower, because three short thin pipes joined end to end is the same as one long thin pipe.

 

[LethalCorpse]

I didn't know Zwickel was David Boon! ???

Makes a lot of sense when you think about it, though, doesn't it?

 

[///]

Only the AHB could take a question to such lengths of answer ....