CFC headloss?

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natehilde

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As some of you know, I am putting together my AG equipment. I have been looking at parts required for the CF heat exchanger. My concern is that the headloss through the heat exchanger will overcome the pressure due to flluid height at the bottom of the kettle ultimately resulting in a loss of wort into the primary vessel. This is assuming that the CFC is mounted horizontally due to space considerations. Can anyone please give me some guidance on correct setup of the heat exchanger to minimize loss of wort.
Thanks
Nate
 
There might be a little left in there, but as long as you have enough fluid head to get everything out of the kettle, what's left in the CFC will be minimal.
 
From your description I assume you are using a gravity setup. That is, gravity and siphoning is the only thing moving your wort around. Anyway, once you get a good siphon going, as long as there is at least a small difference in height of the fluid levels, you should be okay. That is, make sure the fluid level in the full fermenter is lower than the fluid level in the kettle. Once it gets going you should be good.
 
Yes, Thank you guys. I understand fluid transfer characteristics. The thing that I am caught up on though is this.

When transfering liquid from one vessel to another using fluid height as the driving head, you notice that when the level is approaching the bottom of the container, the flowrate diminishes considerably. You can safely assume that headloss through a spiraled heat exchanger will be much greater than through a straight tube. (Headloss defined as power loss due to excessive friction) Hence one can assume that the flowrate through the CFC will be nothing but a trickle when approaching the bottom of the container.

My concern is loss of wort during the cooling process due to headloss. I would appreciate help with arrangment/orientation of the heat exchanger to minimize this.

Thanks
Nate
 
Nah, the difference between the coiled pipe in the CFC and a straight pipe is probably barely detectable with lab equipment, if there actually is any difference. Head loss in pipe flow comes from entrance effects (like when the wort flows from the kettle into the pipe), surface roughness, sharp small radius bends (like a 90 degree elbow), and internal restrictions (partially closed valves and things like that).

Head loss is also dependent on flow rate. The lower the flow rate, the less the head loss. So as the flow rate through the CFC drops, there is actually less head loss. In fact below a certain flow rate the factors I mentioned above barely have an effect.

There are a couple of things I would consider. I would try to make sure I get a good drop from the exit of the CFC into the fermenter, even when it's full. That would ensure that there is a good siphon. The other thing I would consider is pressurizing the brew kettle somehow. It wouldn't take much pressure to blow the wort through the CFC. If the kettle was small enough and I had a lid (or an extra lid) laying around, I might try to drill a hole in it and sticking a piece of tubing through the top. Holding the lid down and blowing into the tube would probably be sufficient to blow the rest of the wort out. If you have access to CO2, it would be even easier.

If you have all of the equipment, just test various configurations with water. That way you can make sure everything will work without wasting any precious wort.
 
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