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Invertible water cooler/heater/dispenser- challenging fluid dynamic

Invertible water cooler/heater/dispenser- challenging fluid dynamic

Invertible water cooler/heater/dispenser- challenging fluid dynamic

(OP)
Hi all!

So I'm stuck working on a really unusual engineering product- don't ask why- but this device inverts a 5 gallon water bottle, and at the end of the cycle, I want this water bottle to be dispensing hot & cold water from two separate conditioned reservoirs.

The challenge I'm trying to resolve with this post has to do with a gravity feed (or pump fed- if that works better) system which is typical on a water dispenser.

As we know- if you invert a container of fluid, and submerge the end- you have defined your water level, and the water is contained by the vacuum in the container.  Allowing air into the system via breather tube or otherwise allows for gravity to drive water into your dispense system.

Troubles I'm having include the balance of air/water pressure to allow free flow, and the necessity to keep any reservoirs below the water line at the tip of the bottle.   Any water that enters the air breather tube also tends to create a stop-flow situation.

Anyway- so fast forward to now-- I'm essentially giving up on the natural approach due to limitations observed and the inverting complication, and a limited available length of breather tube/tip.  I do have both a hot and cold reservoir in this thing and it is important that each is filled as completely as possible with water and not air.  I'd like to do this is as cost-effectively as possible, and so one pump with no solenoid switching or valving is preferred.  Since I have two containers, I'm thinking I'll put an air pump to bubble into the bottle and thereby pressurize each reservoir and fill to wherever that pressure dictates.  I will put the dispense line at the top of each so that any fluid arriving through the taps will already mean the reservoirs are devoid of air.

Is that the best solution or should I be pumping water instead of air, or is there a gravity/valve approach I could use without any components required?   

Sorry if this is difficult to visualize, I may make a diagram if anyone is interested in helping me solve this.  I'm off to the lab to test my air pump theory now, but I'd appreciate any feedback from anyone with ideas.
Thanks!
-k

RE: Invertible water cooler/heater/dispenser- challenging fluid dynamic

Why don't you simply "reverse engineer", or more precisely, make an exact copy of, an office hot-cold drinking water dispenser.  I can't manage to see any difference between that and what you are apparently describing above.  Perhaps you could highlight any differences between them, if they indeed do exist.

Let your acquaintances be many, but your advisors one in a thousand'  ...  Book of Ecclesiasticus

RE: Invertible water cooler/heater/dispenser- challenging fluid dynamic

(OP)
Hi- Thanks for the reply!  We did reverse engineer the system from the start- the problems there were that we wanted a higher "waterline" than allowed by the traditional approach which mandates that your highest water level be at the tip of the dispensing bottle.  The other major problem with that design is that our entire dispenser flips over 180 degrees during operation.  So using a gravity based open-air type of arrangement like most dispensers is not an option.

The good news is that forcing air into the bottle via pump is working out better than I expected, and I think the problems it solves justify the extra expense.  I was going to delete this post because it is actually pretty difficult to diagram this all out without a fully understanding of what this product is- however it is at least useful to know that the forced air solution appears to be the best solution in this case.
Thanks again for the help!
-k

RE: Invertible water cooler/heater/dispenser- challenging fluid dynamic

Well... I still can't seem to imagine any differences, but I'm glad you managed to solve your problem.

Let your acquaintances be many, but your advisors one in a thousand'  ...  Book of Ecclesiasticus

RE: Invertible water cooler/heater/dispenser- challenging fluid dynamic

(OP)
Hi,
The difference is in the 1st sentence- the device INVERTS the entire bottle- while coupled to the plumbing system.  Therefore all gravitational factors are 180 degrees to normal.

Thanks for the help!  and don't you worry- this concept has LOTS of problems to solve!  :)

 

RE: Invertible water cooler/heater/dispenser- challenging fluid dynamic

Start with the office dispenser upside down, put the bottle in and flip???

Let your acquaintances be many, but your advisors one in a thousand'  ...  Book of Ecclesiasticus

RE: Invertible water cooler/heater/dispenser- challenging fluid dynamic

Odd, our office water dispenser leaves the bottle inverted (when compared to tradition office water coolers) and it seems to work just fine.  It's an easy load model like the one linked below.

Link: http://www.soleusair.com/soleusair/mw_59.html

RE: Invertible water cooler/heater/dispenser- challenging fluid dynamic

...and ignore me.  Of course, the system I linked to uses a pump and upon re-reading I see that you are trying to avoid that.

RE: Invertible water cooler/heater/dispenser- challenging fluid dynamic

(OP)
Yes, I know... this is definitely not a GOOD idea- but its the kind of project I tend to get stuck with!  :)

The pump solution you linked is superior in every way except maybe novelty.  I only wish the client would agree.

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