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Main
Date: 17 Oct 2006 23:01:23
From: Eric Scantlebury
Subject: CF chiller theoretical question
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Hello All,
I am probably a couple of months away from moving my 5 gallon extract
batches to 10 gallon full boils as I just got my converted keg and will be
spending time with that over the winter but I thought I'd start thinking
about chilling now (As I just got a real deal on 60' of flexable copper -
40 bucks delivered).
My main question would be about the "point of diminishing returns" on the
length of a CF chiller. I would assume that at some point in length the
cold water entering the chiller will reach a heated point at which
efficiency drops exponentially. So, for instance, if I had a 50 foot
chiller possibly at 30 feet or so the hot wort has "equalized" the
temperature of the water to itself and the remaining 20 feet or so little to
no cooling occurs (numbers are just being made up here). Is this the case
or at least a sound theory?
If so, would there be a benefit to running multiple smaller CF chillers in
parallel with one another? The thought occurred to me on the way home. I
have 60' of copper to play with and before I make a 60' CF chiller I was
thinking maybe I should make 3 20' chillers and make an intake manifold to
feed them and an outflow manifold to the fermenter. I'm thinking this may
actually save on water (I'd feed all from the same water source).
Thoughts? Or am I crazy thinking. LOL!
Eric
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Date: 17 Oct 2006 19:08:18
From: The Artist Formerly Known as Kap'n Salty
Subject: Re: CF chiller theoretical question
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Eric Scantlebury wrote:
> Hello All,
>
> I am probably a couple of months away from moving my 5 gallon extract
> batches to 10 gallon full boils as I just got my converted keg and will be
> spending time with that over the winter but I thought I'd start thinking
> about chilling now (As I just got a real deal on 60' of flexable copper -
> 40 bucks delivered).
>
> My main question would be about the "point of diminishing returns" on the
> length of a CF chiller. I would assume that at some point in length the
> cold water entering the chiller will reach a heated point at which
> efficiency drops exponentially. So, for instance, if I had a 50 foot
> chiller possibly at 30 feet or so the hot wort has "equalized" the
> temperature of the water to itself and the remaining 20 feet or so little to
> no cooling occurs (numbers are just being made up here). Is this the case
> or at least a sound theory?
>
> If so, would there be a benefit to running multiple smaller CF chillers in
> parallel with one another? The thought occurred to me on the way home. I
> have 60' of copper to play with and before I make a 60' CF chiller I was
> thinking maybe I should make 3 20' chillers and make an intake manifold to
> feed them and an outflow manifold to the fermenter. I'm thinking this may
> actually save on water (I'd feed all from the same water source).
>
> Thoughts? Or am I crazy thinking. LOL!
>
CF stands for "Counter Flow". I think you mean "immersion" chiller. As a
rule, more surface area is better. I doubt you'll see much of a boost
from multiple smaller chillers, and you'll simply complicate your
plumbing. With a little dexterity you can fashion a single length of
tubing into two coils, one inside the other.
You get a real boost in efficiency from agitating the wort while the
chiller is running. One setup I know of even uses a pump to recirculate
wort in the kettle, vastly shrinking the cooling interval.
For what it's worth, my IC is around 60 feet and gets the wort (6 - 6.5
gals) to within 5 degrees of the cooling water in around 10 minutes or
so. (I also use a CF chiller).
--
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Date: 18 Oct 2006 00:39:16
From: Eric Scantlebury
Subject: Re: CF chiller theoretical question
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"The Artist Formerly Known as Kap'n Salty" <mikey666@666swampgas.666com >
wrote in message news:4535702d$0$5599$c3e8da3@news.astraweb.com...
> CF stands for "Counter Flow". I think you mean "immersion" chiller. As a
> rule, more surface area is better. I doubt you'll see much of a boost from
> multiple smaller chillers, and you'll simply complicate your plumbing.
> With a little dexterity you can fashion a single length of tubing into two
> coils, one inside the other.
>
> You get a real boost in efficiency from agitating the wort while the
> chiller is running. One setup I know of even uses a pump to recirculate
> wort in the kettle, vastly shrinking the cooling interval.
>
> For what it's worth, my IC is around 60 feet and gets the wort (6 - 6.5
> gals) to within 5 degrees of the cooling water in around 10 minutes or so.
> (I also use a CF chiller).
No - I mean counter flow. In either case, between an IC or a CF or for that
matter a PC it should be surface area that "matters", which is the reason
why I'm thinking along this line. Just thinking that the more the water
moves up the CF the hotter and less efficient it gets (And likewise the more
water that moves down through an IC coil the hotter and less efficient it
gets). If I can get the cooling water out cooler while still keeping the
same amount of surface area that the wort is flowing over (be it through or
around) it seems to me that it would improve the efficiency.
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Date: 18 Oct 2006 08:15:56
From: The Artist Formerly Known as Kap'n Salty
Subject: Re: CF chiller theoretical question
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Eric Scantlebury wrote:
> "The Artist Formerly Known as Kap'n Salty" <mikey666@666swampgas.666com>
> wrote in message news:4535702d$0$5599$c3e8da3@news.astraweb.com...
>> CF stands for "Counter Flow". I think you mean "immersion" chiller. As a
>> rule, more surface area is better. I doubt you'll see much of a boost from
>> multiple smaller chillers, and you'll simply complicate your plumbing.
>> With a little dexterity you can fashion a single length of tubing into two
>> coils, one inside the other.
>>
>> You get a real boost in efficiency from agitating the wort while the
>> chiller is running. One setup I know of even uses a pump to recirculate
>> wort in the kettle, vastly shrinking the cooling interval.
>>
>> For what it's worth, my IC is around 60 feet and gets the wort (6 - 6.5
>> gals) to within 5 degrees of the cooling water in around 10 minutes or so.
>> (I also use a CF chiller).
>
> No - I mean counter flow. In either case, between an IC or a CF or for that
> matter a PC it should be surface area that "matters", which is the reason
> why I'm thinking along this line. Just thinking that the more the water
> moves up the CF the hotter and less efficient it gets (And likewise the more
> water that moves down through an IC coil the hotter and less efficient it
> gets). If I can get the cooling water out cooler while still keeping the
> same amount of surface area that the wort is flowing over (be it through or
> around) it seems to me that it would improve the efficiency.
Sorry -- your description sounded like an immersion chiller. I'm still
not sure there would be much of a difference, though -- ultimately it
seems like you have the same volume of water going through the same area
of coil. You may pick up some advantage from being able to add cooler
water in the downstream coils, but then the difference in temperature
between the wort and cooling water would also be less in the downstream
coils. My guess is that any pickup in efficiency would be pretty small,
but then thermodynamics isn't really my thing. Maybe someone better
versed in the physics involved could give you a better answer.
--
(Replies: cleanse my address of the Mark of the Beast!)
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http://www.swampgas.com/robotics/rover.html
Coauthor with Dennis Clark of "Building Robot Drive Trains".
Buy several copies today!
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Date: 18 Oct 2006 18:32:03
From: John 'Shaggy' Kolesar
Subject: Re: CF chiller theoretical question
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On Wed, 18 2006 00:39:16 GMT, <Eric_Scantlebury@verizon.net > wrote:
>
> "The Artist Formerly Known as Kap'n Salty" <mikey666@666swampgas.666com>
> No - I mean counter flow. In either case, between an IC or a CF or for that
> matter a PC it should be surface area that "matters", which is the reason
> why I'm thinking along this line. Just thinking that the more the water
> moves up the CF the hotter and less efficient it gets (And likewise the more
> water that moves down through an IC coil the hotter and less efficient it
> gets). If I can get the cooling water out cooler while still keeping the
> same amount of surface area that the wort is flowing over (be it through or
> around) it seems to me that it would improve the efficiency.
In theory, yes. I'm not sure if it will really make any difference to
the beer though. Sounds like overkill to me.
John.
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Date: 19 Oct 2006 16:51:01
From: sylvan butler
Subject: Re: CF chiller theoretical question
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On Wed, 18 2006 00:39:16 GMT, Eric Scantlebury <Eric_Scantlebury@verizon.net > wrote:
> No - I mean counter flow. In either case, between an IC or a CF or for that
> matter a PC it should be surface area that "matters", which is the reason
Yes.
> why I'm thinking along this line. Just thinking that the more the water
> moves up the CF the hotter and less efficient it gets (And likewise the more
Yes.
> gets). If I can get the cooling water out cooler while still keeping the
> same amount of surface area that the wort is flowing over (be it through or
> around) it seems to me that it would improve the efficiency.
Yes. For "coolant" efficiency (making maximal use of coolant, or in
other words, using as little coolant as possible.)
There are several types of efficiency... Cooling as fast as possible
(time efficiency), cooling as much as possible (cooling efficiency) and
using as little coolant as possible (coolant effiency). (In all cases I
assume that you get the job done, if you don't you have 0% efficiency in
whatever you are trying to optimize.)
It sounds like you want "coolant" efficiency.
OK, so what to do? Let's think about this...
With counterflow, cold coolant enters and cold 'brew' exits at the same
end of the chiller. The other end is opposite. The maximum coolant
(not cooling) efficiency is when the coolant reaches the temperature of
the incoming brew just as the coolant exits. (If the coolant reaches
max temperature before the exit, the rest of the chiller is wasted. If
the coolant does not reach max temperature before exiting, coolant is
wasted.)
For a given chiller, you can optimize coolant efficiency by altering the
flow of hot brew or cold coolant or both. Increased coolant flow will
tend to reduce coolant output temperature. Increased 'brew' flow will
tend to increase coolant output temperature. (In both cases flow
outside a certain range might have no or even the opposite effect.)
Hopefully I got all that right. :)
My recommendation would be to pick a CFC length that has been successful
for others, 20ft is probably just fine. Build that chiller. Use it.
Adjust the flow of cooling water input to see how the coolant output
temperature changes. If the output wort isn't cool enough, increase
coolant flow. If output coolant is too cool, reduce coolant flow.
Now you can decide if you need more...
If you cannot get both cool wort and hot coolant, you need more CF
length for coolant efficiency. (Putting two in series is fine.)
If the wort doesn't flow fast enough, then you need more CF capacity
(put two in parallel, or use bigger pipe which means you will also need
more length).
sdb
--
Wanted: Omnibook 800 & accessories, cheap, working or not
sdbuse1 on mailhost bigfoot.com
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Date: 20 Oct 2006 03:36:43
From: Eric Scantlebury
Subject: Re: CF chiller theoretical question
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"sylvan butler" <ZsdbUse1+noZs_0610@Zbigfoot.Zcom.invalid > wrote in message
news:slrnejg0al.uc9.ZsdbUse1+noZs_0610@sdba64.internal...
> On Wed, 18 2006 00:39:16 GMT, Eric Scantlebury
> <Eric_Scantlebury@verizon.net> wrote:
> OK, so what to do? Let's think about this...
>
> With counterflow, cold coolant enters and cold 'brew' exits at the same
> end of the chiller. The other end is opposite. The maximum coolant
> (not cooling) efficiency is when the coolant reaches the temperature of
> the incoming brew just as the coolant exits. (If the coolant reaches
> max temperature before the exit, the rest of the chiller is wasted. If
> the coolant does not reach max temperature before exiting, coolant is
> wasted.)
>
> For a given chiller, you can optimize coolant efficiency by altering the
> flow of hot brew or cold coolant or both. Increased coolant flow will
> tend to reduce coolant output temperature. Increased 'brew' flow will
> tend to increase coolant output temperature. (In both cases flow
> outside a certain range might have no or even the opposite effect.)
>
> Hopefully I got all that right. :)
>
> My recommendation would be to pick a CFC length that has been successful
> for others, 20ft is probably just fine. Build that chiller. Use it.
> Adjust the flow of cooling water input to see how the coolant output
> temperature changes. If the output wort isn't cool enough, increase
> coolant flow. If output coolant is too cool, reduce coolant flow.
>
> Now you can decide if you need more...
>
> If you cannot get both cool wort and hot coolant, you need more CF
> length for coolant efficiency. (Putting two in series is fine.)
>
> If the wort doesn't flow fast enough, then you need more CF capacity
> (put two in parallel, or use bigger pipe which means you will also need
> more length).
>
> sdb
Good post. So basically I'm going to have to experiment with this in any
case. :)
My water coming through the chiller will be cold (probably in the 40 to low
50 degree range as it is coming right out of the ground. I don't bother
using ice in my cold water even during the summer). So I might start with a
30 foot chiller and play with the flows both ways to see what I get. If I
understand what your saying I can increase or decrease waterflow and also
play with the flow of wort and maybe make an optimal. IF not then I can
play with either a series or parallel chiller with the remaining 30' of
copper. I just really am trying to conserve water and hopefully not burn
out my well pump.
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Date: 20 Oct 2006 10:37:21
From: Mark R
Subject: Re: CF chiller theoretical question
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"Eric Scantlebury" <Eric_Scantlebury@verizon.net > wrote in message
>
> My water coming through the chiller will be cold (probably in the 40 to
low
> 50 degree range as it is coming right out of the ground. I don't bother
> using ice in my cold water even during the summer). So I might start with
a
> 30 foot chiller and play with the flows both ways to see what I get. If I
> understand what your saying I can increase or decrease waterflow and also
> play with the flow of wort and maybe make an optimal. IF not then I can
> play with either a series or parallel chiller with the remaining 30' of
> copper. I just really am trying to conserve water and hopefully not burn
> out my well pump.
With that temperature water you shouldn't have much problem getting 30' to
work for you. Start with the water running slow. You only need the wort temp
to be low 60's for an ale so just run the wort through at a speed that gives
you that temp output. Run your water into a drum so you can use it later for
gardening.
As far as chiller efficiency, we used to look for between 20 and 30 degrees
spread on shipboard chiller systems, the closer to 30 the better. I'd guess
that if your wort is discharging at the desired temp (60 degrees), and your
CFC discharge water is about 20 - 30 degrees lower than the hot wort going
into your CFC, then you have a balanced system.
Let's say your hot wort is still 200 plus and your getting cooled wort at 60
deg, but your CFC water discharge is 150 deg. You could slow down the
cooling water flow but then the cooled wort temp would rise so you'd have to
slow down the wort flow too. Or you could speed up the wort flow and the
water discharge would rise but then you would need to speed up the water
flow to keep the cooled wort at 60.
The other way to balance the system would be to start with a long CFC (at
least the 30 ft you were talking about) and adjust both water and wort flow
to levels that you are comfortable with. Then start shortening the CFC until
you reach either the 60 degree output wort temp or a CFC discharge that's
about 20 deg below brew pot temps. Then tweak one or both of your flows as
needed.
Mark R
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Date: 20 Oct 2006 16:12:08
From: sylvan butler
Subject: Re: CF chiller theoretical question
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On Fri, 20 2006 10:37:21 -0500, Mark R <marknorayspam@noev1spam.net > wrote:
> Let's say your hot wort is still 200 plus and your getting cooled wort at 60
> deg, but your CFC water discharge is 150 deg. You could slow down the
> cooling water flow but then the cooled wort temp would rise so you'd have to
> slow down the wort flow too. Or you could speed up the wort flow and the
> water discharge would rise but then you would need to speed up the water
> flow to keep the cooled wort at 60.
That is true, unless he has extra chiller capacity (ie it is longer than
required). If it is longer, the discharge coolant would reach max
temperature earlier, but still leave time for the wort to cool before
exiting. Such extra capacity (an "unbalanced" system) isn't good if you
make a lot of them (costs more), or if you have space limitations (it
will be larger). Since this is a "one off" product, with limited
coolant supply, the cost of extra chiller capacity is small compared to
using extra coolant.
or think of it this way... If you have no chiller, adding 10ft of
chiller will work wonders. The second 10ft won't do as much, and the
third 10ft will do even less. those diminishing returns are what you
try to minimize by a "balanced" system.
The O.P. is instead trying to minimize coolant usage.
sdb
--
Wanted: Omnibook 800 & accessories, cheap, working or not
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Date: 20 Oct 2006 16:02:46
From: sylvan butler
Subject: Re: CF chiller theoretical question
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On Fri, 20 2006 03:36:43 GMT, Eric Scantlebury <Eric_Scantlebury@verizon.net > wrote:
> Good post. So basically I'm going to have to experiment with this in any
> case. :)
Yup. :)
It is either experiment, or do LOTS of UGLY math... The biggest problem
is calculating the heat transfer efficiency of the chiller.
The degrees moved from hot to cold will be essentially equal. In other
words, coolant at 50F, 10gallons of hot at 210F, target is 60F. You
need to remove 150 degrees from 10 gallons or 1500 degree-gallons. In
theory you could do that by heating 1500 gallons of coolant by one
degree, or 1 gallon of coolant by 1500 degrees. (Obviously reality
interferes when you are using passive heat transfer from water to water.
:)
In an ideal world you could instantly transfer the heat from 10g of hot
water to 10g of cold water. More realistically, you will be doing good
if you can cool your wort by transferring the heat to 20g of cold water
(raising it 75F) in some reasonable time.
> using ice in my cold water even during the summer). So I might start with a
> 30 foot chiller and play with the flows both ways to see what I get. If I
> understand what your saying I can increase or decrease waterflow and also
> play with the flow of wort and maybe make an optimal. IF not then I can
Exactly. Try to just adjust one, probably coolant is easiest. Only
adjust the wort if you must.
> play with either a series or parallel chiller with the remaining 30' of
Yes.
Series chiller for more heat transfer (if you can't get hot enough
coolant (or cold enough wort) out).
Parallel chiller for faster heat transfer (if it takes too long at the
highest flow rate you can achieve).
> copper. I just really am trying to conserve water and hopefully not burn
> out my well pump.
For maximum coolant savings, you want the coolant output temperature as
high as you can get it... (which will be almost the same temperature as
the incoming hot wort). Hopefully when playing with the flows you can
get high enough flow to be getting:
1) cool wort out
2) coolant out that is significantly less hot than the incoming wort
and then decrease coolant flow (or increase wort flow) until the exiting
coolant does not get any warmer.
I expect you will find it far easier than all this talk and worry. :)
sdb
--
Wanted: Omnibook 800 & accessories, cheap, working or not
sdbuse1 on mailhost bigfoot.com
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Date: 20 Oct 2006 23:35:55
From: Eric Scantlebury
Subject: Re: CF chiller theoretical question
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"sylvan butler" <ZsdbUse1+noZs_0610@Zbigfoot.Zcom.invalid > wrote in message
news:slrnejihs6.8f0.ZsdbUse1+noZs_0610@sdba64.internal...
> I expect you will find it far easier than all this talk and worry. :)
I hope so. :)
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Date: 18 Oct 2006 13:12:17
From: Scott L
Subject: Re: CF chiller theoretical question
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The Artist Formerly Known as Kap'n Salty wrote:
> Sorry -- your description sounded like an immersion chiller. I'm still
> not sure there would be much of a difference, though -- ultimately it
> seems like you have the same volume of water going through the same area
> of coil. You may pick up some advantage from being able to add cooler
> water in the downstream coils, but then the difference in temperature
> between the wort and cooling water would also be less in the downstream
> coils. My guess is that any pickup in efficiency would be pretty small,
> but then thermodynamics isn't really my thing. Maybe someone better
> versed in the physics involved could give you a better answer.
I think this discussion is missing the concept of COUNTER flow. The
coolant water enters at the point where the wort EXITS. This means that
the wort at the end of the chiller is always in contact with the
coldest water possible. Adding another downstream coil doesn't help
anything -- the downstream direction is always the direction of
decreasing coolant temperature anyway.
Adding another coil simply serves to increase the total surface area
the wort comes in contact with. Additionally it is going to double the
pressure drop across the cooling system which means his pump is going
to be more stressed (and stressing the pump seems his prime concern).
I think if he's willing to drop the money on it, a convoluted CFC is
probably the best solution. As everybody seems to understand, surface
area is the real parameter here, and a convoluted CFC increases the
surface area the wort "sees" by breaking up the laminar flow, without
actually changing the "real" surface area. Result is, coolant water is
used more efficiently (you don't get a warm laminar flow near the
inside tube and a colder flow away from it, it's all stirred up
together) and you can flow the wort through much faster. Flow wort
faster -- > less time spent cooling --> less stress on the pump.
Scott
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Date: 18 Oct 2006 18:29:46
From: John 'Shaggy' Kolesar
Subject: Re: CF chiller theoretical question
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On Tue, 17 2006 23:01:23 GMT, <Eric_Scantlebury@verizon.net > wrote:
> My main question would be about the "point of diminishing returns" on the
> length of a CF chiller. I would assume that at some point in length the
> cold water entering the chiller will reach a heated point at which
> efficiency drops exponentially. So, for instance, if I had a 50 foot
> chiller possibly at 30 feet or so the hot wort has "equalized" the
> temperature of the water to itself and the remaining 20 feet or so little to
> no cooling occurs (numbers are just being made up here). Is this the case
> or at least a sound theory?
It's probably a sound theory, but I don't know what lengths are involved.
IE, it may be a moot point for the size chillers we're talking about.
> If so, would there be a benefit to running multiple smaller CF chillers in
> parallel with one another?
Lots of people use standard CF chillers with 10 gallon batches and it
works fine. I don't think there's any major need to try and use multiple
ones unless you just want to try saving some extra time at the end of your
brew day. I believe one chiller should be sufficient. You may save a
little bit of water and some time by using two, but it's probably nothing
really significant. It's up to you though. Using multiple chillers shouldn't
hurt anything.
John.
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Date: 18 Oct 2006 15:31:42
From: Eric Scantlebury
Subject: Re: CF chiller theoretical question
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"John 'Shaggy' Kolesar" <spam@shagg.net > wrote in message
news:slrnejcssi.6k2.spam@weizen.shagg.net...
> It's probably a sound theory, but I don't know what lengths are involved.
> IE, it may be a moot point for the size chillers we're talking about.
>
>> If so, would there be a benefit to running multiple smaller CF chillers
>> in
>> parallel with one another?
>
> Lots of people use standard CF chillers with 10 gallon batches and it
> works fine. I don't think there's any major need to try and use multiple
> ones unless you just want to try saving some extra time at the end of your
> brew day. I believe one chiller should be sufficient. You may save a
> little bit of water and some time by using two, but it's probably nothing
> really significant. It's up to you though. Using multiple chillers
> shouldn't
> hurt anything.
Well, I live in the boonies and I'm always concerned with my water situation
and running my pump wide open for 20 to 30 minutes is really not that
appealing. I don't have a standard well, just a point and I pull water with
a pump instead of pushing it and believe me, those pumps are expensive when
they burn out. LOL!
My thoughts would be to limit the amount of water usage by limiting the flow
rate of the water while still getting the same amount of cooling by
increasing the surface area of wort to copper during the "Sweet spot" of the
temperature curve.
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Date: 18 Oct 2006 19:43:53
From: John 'Shaggy' Kolesar
Subject: Re: CF chiller theoretical question
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On Wed, 18 2006 15:31:42 -0400, <test@test.com > wrote:
> My thoughts would be to limit the amount of water usage by limiting the flow
> rate of the water while still getting the same amount of cooling by
> increasing the surface area of wort to copper during the "Sweet spot" of the
> temperature curve.
Limiting the flow will more efficiently use the water, but it will make
your chilling times longer. In your situation, this makes sense though
and is probably the best way to address it.
I think trying to do both slowing the flow and increasing the surface area
is just going to make the "sweet spot" smaller. I'm not sure if you'll get
any net benefit from it regarding water usage.
John.
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Date: 21 Oct 2006 22:28:38
From:
Subject: Re: CF chiller theoretical question
|
sylvan butler wrote:
> On Fri, 20 2006 03:36:43 GMT, Eric Scantlebury <Eric_Scantlebury@verizon.net> wrote:
> > Good post. So basically I'm going to have to experiment with this in any
> > case. :)
>
> Yup. :)
>
> It is either experiment, or do LOTS of UGLY math... The biggest problem
> is calculating the heat transfer efficiency of the chiller.
>
> The degrees moved from hot to cold will be essentially equal. In other
> words, coolant at 50F, 10gallons of hot at 210F, target is 60F. You
> need to remove 150 degrees from 10 gallons or 1500 degree-gallons. In
> theory you could do that by heating 1500 gallons of coolant by one
> degree, or 1 gallon of coolant by 1500 degrees. (Obviously reality
> interferes when you are using passive heat transfer from water to water.
> :)
Oooh, oooh. Ugly math time. Well, not ugly math, but memories from my
physics and chemistry classes of about 30 years ago. I touched on this
on another thread a few minutes ago, so forgive me for duplicating part
of this.
Your numbers will work if both fluids are water, but they are not. The
wort has a fair amount of sugars and traces of complex carbs and
protiens disolved in it. Therefore the specific heat of the wort is
not 1 like the water is, but higher. I have NO IDEA what the SH for
wort is, and it will vary for each wort since they all have different
densities. Lets just say that the average wort has a SH of 1.2. Once
again I have no idea if this is realistic or not. In that case you
don't have 1500 degree/gallons, but 1800 for water as the coolant. See
where this is going? The mass times the specific heat will tell you
how much water you would need to cool the wort assuming 100%
efficiency. Guess what, the real world doesn't get those kinds of
efficiencies, especially in a passive heat transfer system like a IC or
CFC. If the water is coming out really close to the temp of the wort
the only way to cool it faster would be to move more water in the same
amount of time, and that may actually need a longer chiller if there is
no slack in the system. i.e. the water reaches wort temp just as it
exits the chiller. If the water reaches the wort temp, say 15' from
the end of the chiller, uping the flow rate can net you some time.
<snip >
>
>
> > copper. I just really am trying to conserve water and hopefully not burn
> > out my well pump.
>
> For maximum coolant savings, you want the coolant output temperature as
> high as you can get it... (which will be almost the same temperature as
> the incoming hot wort). Hopefully when playing with the flows you can
> get high enough flow to be getting:
> 1) cool wort out
> 2) coolant out that is significantly less hot than the incoming wort
You want the coolant as close to the wort temp as you can to minimize
the amount of coolant. If you need to minimize the coolant and you can
absorb a bit of cost, make a system that is a closed loop. 3 gallons
of cool well water in a 5 gallon bucket and 2 gallons of water frozen
in whatever shape you want. Ziplock bag form may be a fairly cheap way
to go. Put a pump in the bucket and recirculate the water through the
chiller. The important thing is that the heat come back from the
chiller and be used to melt the ice, not recirculate imediatly back
into the chiller. The state change of the ice to liquid will eat a lot
of the heat. Your best bet there would be to stir the water in the
bucket so the maximum water volume contacts the ice surface area.
>
> and then decrease coolant flow (or increase wort flow) until the exiting
> coolant does not get any warmer.
Or in the case of the closed loop system with ice, make sure that the
water entering the chiller is as close to 32f as possible and the water
returning from the chiller is as close to wort temp as possible.
>
> I expect you will find it far easier than all this talk and worry. :)
>
> sdb
>
> --
> Wanted: Omnibook 800 & accessories, cheap, working or not
> sdbuse1 on mailhost bigfoot.com
Bryan
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