A TEC assisted CPU waterblock to prevent moisture build up and a TEC failure disaster.
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A TEC assisted CPU waterblock to prevent moisture build up and a TEC failure disaster.
I think I see what you are going for here. Are you planning to use two loops?
This seems overcomplicated and inefficient to me. I do like it when people think up something original though.
Isn't condensation still going to be an issue since the chiller water is making contact with the metal exposed to the CPU which is exposed to the outside? :shrug:
I think the water at room temperature doesn't have the time to get chilled.
The CPU is hot and it only gets chilled at the center where there is immediate contact between the central copper piece of the 4th plate and the third plate.
Scarlet Infidel
No, One loop is enough. A splitter in and a join out.
This way the water never gets too cold.
So the same water loop is in contact with both the cold and hot side of the TEC?
Yes. Room temperature water enters both chambers and gets out to enter the same loop. The CPU gets chilled from direct copper contact mainly.
The first part is delrin and other three parts are copper.
The last one (on the CPU) is only trimmed at three sides just to fit the 3rd plate and to create a path for the water.
This way it is easy to drill holes near the base of the plate.
How will you make sure the water is at room temperature? The net effect of the peltier here it to increase the water temperature at the expense of electricity.
If you power a TEC with no cooling on the hotside within seconds it will burn out because the room temperature on the hotside is insufficient to cool it.
If you plan to cool a TEC with room temperature water you are pretty much doing a similar thing !!
It will cool it to a small degree due to the water movement but not enough to prevent it's demise.
The difference between the hot and cold sides will be too large.
The TEC will heat the water in the top of the unit you will not be able to maintain it at room temp so your loop will just get warmer and warmer. This happens in all single loops that pass both the cold and the hotside of a single TEC. This will also cause the TEC to burn out if you try to cool it with warm water. This is doomed to fail.
Result - dead TEC.
One hell of a lot of work for nothing......
To prevent condensation...simply insulate.
To prevent CPU loss due to TEC failure...simply set a temp limit in the bios or in a program such as realtemp or coretemp to turn off the machine when TEC fails...
Much easier than what your proposing...
The water from the lower chamber (over the CPU) should keep its room temperature at the outlet.
Both the CPU and the TEC try to alter the water temp.
In case we give too much power on the TEC, the water in the lower chamber gets colder, but the water in the upper chamber gets hoter.
The water from both chambers' outlets mix together.
Then they enter the radiator.
Low noise fans on the radiator should be enough to keep the water in room temp.
Though I might insulate the middle of the CPU slot.
Just in case.
Water at room temp is enough to cool a TEC.Quote:
Originally Posted by zipdogso
You won't keep the water at room temperature (it's technically impossible with the setup you describe).
The only way the peltier could possibly reduce the CPU temperatures is if the heat conduction formt he peltier through the copper is greater than the heat conduction into/out of the water just above the CPU. This means when the peltier is off the block would need perform very badly to even get the design to work. Overall it will just give worse temperatures I'm afraid.
So you plan to underpower the TEC. (that's why room temp water will cool it yes ?)Quote:
Originally Posted by Marios
Because your hotside cooling will be insufficient, if it doesn't eventually kill the TEC, IT WILL HAVE A HIGH TEMP. DELTA. ie the difference between the hot and coldsides. At a high temp delta your heatpump will be minimal and will not effect much cooling so the hot CPU (supposedly kept in check by the TEC.) will heat the water in the loop and your loop will get warmer and warmer.
Depending on you underpowering of the TEC (less than about 60%)with a high temp. delta the TEC will not even work.
Trust Scarlet and me your plan is a no-go.
Room temperature coolant will cool a TEC but insufficiently (that's the point I did'nt get across.) with your one loop it will not remain room temp it will get warmer.
You said "In case we give too much power on the TEC, the water in the lower chamber gets colder, but the water in the upper chamber gets hoter."
The problem is the water in the upper chamber will get very much warmer than the lower chamber will chill - in general the heat given off by the hotside will be at least 25% more than the amount of cooling from the coldside.
Your loop will get warmer how ever you look at it but really it is all a moot point because to achieve your planned result ....
To prevent condensation...simply insulate.
To prevent CPU loss due to TEC failure...simply set a shutdown temp in the bios or in a program such as realtemp or coretemp to turn off the machine when TEC fails...
Scarlet Infidel
Even simple - unaided watercooling is enough to make a TEC work well, as we can see from other projects.
With a 45°C Delta, we need to keep the hot area at 50°C to get 5°C on the cold area.
Water is power.
With this waterblock halve the water flow through both CPU chambers is hot, halve is at room temp and they mix together.
Then we also have the refrigerator to further cool the water.
This helps to achieve much lower tmps at the CPU area with much less moisture build up and much less noise than regular designs.
And it even cools the CPU in case of a TEC failure.
No need to shut down immediately to avoid a disaster and restore the failed TEC.
Though in case of a watercooling failure (ie pump) we do have a big big problem.
The reason I wrote this post here is to avoid someone elso come and patent the same idea.
It is now an open project for anyone to try and build.
What is your avatar about?
It looks like a peltier sandwich with two waterblocks.
The avatar is a model of a peltier water chiller I started making. The idea of it was to be cheap and low power and not to cool the water beyond the point where condensation occurs. The design had too many compromises really and I never finished it. Here is the thread if you want more detail.
I don't want to put you off innovating and coming up with new designs and I don't want to be rude. I will not pursue this any further but to say the design just will not work like you want it to. Feel free to make one and prove me wrong.
OK I see...Quote:
Originally Posted by Marios
My feelings also....but there are one or two points in your last post which i don't think are rightQuote:
Originally Posted by Scarlet Infidel
1.)
"With a 45°C Delta, we need to keep the hot area at 50°C to get 5°C on the cold area. " Here you have tailored the figures to fit your ideal, unfortunately it is rather fanciful, in real life it won't happen. without any apparent heat attached to the coldside (It looks to me like there is an intended gap between plates 3 - 4.) the coldside will be colder than you imagine and with only minimal cooling on the hotside (room temp coolant) I can see a temp delta larger than 45º. Even if you theory was correct (45º delta.) it would result in a heatpump of only 30% Qcmax or less ie very little cooling.
2.)
"Then we also have the refrigerator to further cool the water."
What refridgerator ?? The TEC is merely a heatpump taking heat from the lower chamber and dumping all that heat plus the heat generated internally by the TEC into the the top chamber it is a heat mover it does not actually do any heat lowering in fact as I already said it creates more heat in use. This is why using only one loop will just get warmer and warmer.. The heat will only be removed from the system if you use a dedicated hotside loop to do so.
I realize that this is your "baby" but you have blindfolded yourself in your willingness for this to work.
why not stick something like glycol between the CPU die or IHS and the TEC then cool the top with a normal water cooling loop. The problem with your current design is that TECs will also produce more heat than the amount of energy they can displace. So no matter what if you had a closed loop between hot and cold side it would always heat up. I realize that you have probably tried to think this through but I think you need to read up more on how TEC's operate and function.
I though it was something like that.Quote:
Originally Posted by Scarlet Infidel
The hot side is the fridge of the watercooling loop. There we have fans to remove excess heat. There we not only have warm water going in from the upper chamber of the "TEC assisted CPU waterblock" but cold from the lower chamber too.Quote:
Originally Posted by zipdogso
There are no gaps between the plates. I left them just for illustration purposes. Though we should use thicker rubber to the full extend between the second and third plates to prevent heat transfer to the lower chamber.
if you're going to have 2 different heat signatures to cool and one of them is optional .. means you can switch on and off the TEC rite?
maybe you need to incorporate heatpipes, it's technically purchasable .. and it's quite easy to bend .. i broke a few .. lol
what do you think?
it's just a random brainstorming
Attachment 95780
but keep in mind .. watercool isnt bout 1 pass of water .. it requires .. lotsa loops
Quote:
Originally Posted by Scarlet Infidel
I read most of your project thread... shame you didn't finish it. :( It looks like it would work at least a little... were you so convinced that it would not work? You never say why in the linked thread.
Also has anyone else tried to make a tec waterchiller to get sub ambient temps... obviously Coolit has with their products... My dilema is... I am desperatly seeking to find or make a stand alone tec watercooler or tec assisted radiator system to cool an i7 below at or below ambient. The Boreas unit from Coolit breaks even on the i7 and water cooling surpasses it at a certain point of overclocking... I'll see if I can find the thread.
Seems to me... there is a market for a sub-abient cooler/motherboard combo. Couldn't the motherboard manufacturers make a MB that would be protected from condensation? There is a need here that is not being filled and I'm convinced that it is totally possible!
at least a cooler that takes the cpu down to or just a hair above ambient... Please!
The chiller in the thread was mainly a cheap and easy to build prototype so I could experiment without wasting too much money. The main reason I stopped work on it is simply that I never have time and I am rarely at home where my tools are (I'm a University student).
I have recently starting looking into parts for a more expensive but better chiller based in the same principles and using many of the same parts. I hope to have a few days free over Easter to get something going. I definitely something like an improved Boreas would keep many people happy. Unfortunately copper and TEC prices seem to have gone through the roof since I got mine and I believe that using lots of TECs is the key.
Getting sub ambient temps with a TEC is not a big problem....Quote:
Originally Posted by Overclocker333
The problem is every Tom, Dik, Harry and his dog wants to stay above the dew point and fine control like that is a problem....not unsurmountable, but a problem none the least.
If you just want to cool and keep going sub ambient and depending on design etc even sub zero (no silly figures though - it's not phase !), within reason that is what you use TECs for. The coolit and boreas units use very small TECs undervolted....they have to because the current limit on a molex is for safety 7-8amps. To make their units available and easy to connect for all they have to use molex connection.
Build the chiller yourself and you no longer have this restriction you can undervolt high power TECs to get the efficiency and then multiply them to get back up to a sensible heat pump. So in general you would use at least 4. Theoretically you could build a coolant chiller for any heat load so i7 and high end cards are no longer a problem...HOWEVER you need to know a little about TECs, small electrical circuits, heatflow etc and be reasonably able on the DIY front.
This is a relatively "new avenue" so it helps if your a bit innovative we have yet to see designs that work well.
Once people stop being so concerned with the dew point and just do the sensible thing and insulate then perhaps we can get on and find some good designs for TEC water chillers.
I think you should separate cpu cool and tec cooling.Quote:
Originally Posted by Serpentarius
In my system aiming for the water to be at ambient or just below (dew point) was for a couple of reasons. Firstly so I don't have to worry about condensations as you say. However the main reason was purely because I wanted a power efficient system and the cooler you go the more power you use and this seemed like the best trade-off.Quote:
Originally Posted by zipdogso
In that case I feel your concerns were a little misguided.Quote:
Originally Posted by Scarlet Infidel
Using multiple undervolted TECs (which achieves a good COP.) going sub zero doesn't affect things greatly. If you look at ferrotec performance charts and start by typing a reasonable hotside temp say 30ºC pick an input power (undervolt to 25% or less.)and average delta, then using the same charts enter -15 and recalculate and use the same input power and delta. The current draw rises slightly and obviously as a result of this the COP reduces slightly but it is fairly negligible. A COP of least 2 is still achievable.
Of course in the normal course of things you would have a job achieving a hotside of -15 i an really only saying this to illustrate a point that your concerns are not necessarily correct.
I think we are talking about different things here. Lets start with a magic system that cools the hotside to a constant 30c regardless of load. To get a COP of 2 you are limited to a dT of around 15c. This means with no thermal resistance (not possible) the cold side loop would be 15c (ie probably just above dew point for me). these are the kind of numbers I was playing with in my system.
Now lets say you want to reach zero. Now you need a dT of 30c (actually more because of the extra heat form the pelts but we will assume you can compensate). Now you get a COP of around 0.75. In reality with the added heat load you would probably only get 10c cooler for 2-3 times the power. It just doesnt seem worth it to me.
Yes I see what your saying and it is perfectly true for a single TEC.Quote:
Originally Posted by Scarlet Infidel
That is not what I was talking about...I was talking about multiple undervolted TECs. Each one carries a portion of the heat load, the hotside temp is a lot lower (so long as you give it good cooling.), the delta max is lower, the delta temp is lower. The general theory is you need a good number of TEC's dependent on your heatload...certainly you need in excess of 4. It certainly helps if your general ambient is not too high. On reflection perhaps Subzero is not really realistic but quite a way below dew point (single figures.) is easily possible...you would need a chiled ambient for subzero.
OK i was going a bit too far with the hotside of -15ºC but I only quoted that to show what happens. It shows you just lose a little bit of COP..a litttle bit..not like 1.5.
This is the theory Uncle jimbo was bandying about.
My example was for a single TEC handling 20w or so, for example 10 would be needed for 200w.
My chiller has 10 TECs in it, I'd still prefer more. I still think you lose a lot of COP for high dTs. Could you give an example to show what you mean (mention type and number of TECs, voltages, heatload etc)
Well I can give an example but it's not actually a working at the moment...I am waiting on some temp sensors then a bit of wiring and soldering and finally some copper parts which I have been forced to make myself, cause I cant find anyone to do it for me !!Quote:
Originally Posted by Scarlet Infidel
My TECs are 26316's (31.6v - 16 amps) with a qcmax of in excess of 300w at 27ºC (The manufacturers words NOT mine...couldn't even give me a proper performance chart !!!)
Well the nearest thing on ferrotec is here:- http://www.ferrotec.co.uk/index.php?...ail&mod_id=118
UJ said the figures need adjusting by 263/242 = 1.0867 but i am happy to take the 8v figures but actually run at 7v or just over - shouldn't be far wrong.
After discussion with Uncle Jimbo he reckoned with watercooling a good ballpark figure would be hotside = ambient +10ºC and dT 15-20ºC with the dT being conservative.
The supply I'm using is variable 4-16v with a 22amp max.
Average room ambient at the mo is about 22º but it is dead easy to get it lower so for this take 22º+10 =32º hotside.
So adjust the ferrotec calc hotside to 32º
8v gives about 4amps for pump of 70w and 90-100w rejected (bare in mind 100w can be cooled quite well with quality heatsink /fan arrangement.) and a COP of 1.5 with a coldside just over 10º reducing the ambient a bit could swing it to single figures.
I only 4 ( 2series/2 parallel - 7v 4amps each.) of these so total pump = just under 300w for just over 110w in. I could use more to improve heatpump and reduce input power by another volt or so.
In my final project of which this is a small part the ambient/hotsides and dT will be lower and obviously the COP higher.
Im impressed by those numbers and they all look right to me. The only TECs I can get hold of dont have anywhere near as good properties as that. With a COP of 1.5 and dT of 15-20 my units can only pump about 10w so even though I have 10 of them this isnt going to be very useful.
Of course it is important to bear in mind that the chiller I was building was designed for acceptable performance at very low cost (not much more than a straight watercooling system). I have clearly lost sight of what is achievable with higher end parts. Where did you get them from? How much were they and how many do you have?
I got them from Hebei I.T.Quote:
Originally Posted by Scarlet Infidel
http://www.hebeiltd.com.cn/?p=z.peltier.pricelist
They are the last ones at the bottom of the list....
In my view they are unfortunately about the only ones worth buying.
Luckily...or not as the case may be ....They don't have a distributer in UK so I could place an order for just $99 (the normal limit is $250.) , so I ordered 4 there was a premium for a small order so in the end I paid $107 and $33 shipping, they came in fast only about 5 days...then 2-3 weeks later I got an invoice from the shippers for another GBP 15 for import/VAT !!! This was last year when the rate was a bit better so the 4 ended up costing about GBP 95. More than I initially hoped but far better than Kryotherma prices !!! I'd like to get some more but the rates not so favourable now...need a bit more available cash.
They are very impressive. My cheap TECs were £17.50 for 10 including postage etc. Bit of a bargain but now about double that I think (I was thinking about getting another ten).
If we assume you have flow rate of 200 Liters per hour:Quote:
Originally Posted by Serpentarius
200/3600=0,055L/sec
water weights about 1kg per liter so and it has thermal capacity of 4,19kj/kg*k so...
0,055*4190=232W/K
So you need 232 watts of power to warm up the water one kelvin. Water doesnt get _that_ hot after all does it?
heh I was just looking for something like this today, but for an Air heat sinkQuote:
Originally Posted by ilkkahy
what's the formula for all this that's what I'd like to know
it's like you need to an actuary to figure these tec's out completely
What are asking here?Quote:
Originally Posted by demonkevy666
The calculation you highlighted is merely a calculation for the power required to heat or cool water by 1 degree.
It has nothing specifically to do with TEC's or air heat sinks.
Those are very basic and easy calculations of heat removal, which i think people should do at the beginning to get the idea whats possible and whats not.
For air heatsink:
Air weights 1,29kg/m^3, it has thermal capacity of 1kj/kg*K
If we have airflow of 100m^3/h trough the heatsink... = 100/3600=0,0277m^3/s
Air weights 1,29kg/m^3 so 1,29*0,0277=0,0358kg/s =mass flow
0,0358*1000=35W/K
So you need 35 watts to heat air for 1K. With 350 watts heatload the air would heat 10K while passing heatsink.
What does this have to do with what is being discussed here. We're just trying to make a TEC waterblock not an air heatsink. I realize the same principles follow but it's not particularly relevant.
Well someone said that certain waterblock model requires lots of loops due high heat output of the system (i assume?). I think that its bit wrong unless you have very very low flowrate. Also demonkevy wanted to know how it goes with air heatsink so i answered to him.
Anyway..
I have thought about this tec assisted cpu waterblock sometime myself too. The idea is not to try to move all cpu heatload with the peltier. It would be possible to get slightly lower temps than with just a normal waterblock but i dont think that its eventually worth the wasted electricity and complexity of the system. Its intresting concept though.
I made quickly picture of the version i have thought about testing if i build water cooling rig some day.
http://img17.imageshack.us/img17/7561/peltierblokki.png
I would propably use Thermaltake 120 copper version as heatsink and Drift-08 peltier at 12v as i happen have to some of those at my junkpiles.
So the peltier+heatsink would move heat from the waterblock and the water. The trick would be to optimize the ratio which to cool more (water or the waterblock/cpu). It might seem stupid at first but having thought this more i think there is kinda fun/intresting possibility to optimizing and tinkering with this kind of "hybrid" system.
i've thought of these too. it would be interesting to see how much of a difference they could make ... i hink construction is the real issue you need to make it out of a single block of copper. NO covers
just for my 2 cents....ilkkahy..I think your on the nod.Quote:
Originally Posted by ilkkahy
I have been working on a similar idea for TEC cooling. This is the principal I have been thinking about for the last 7-8 months.
I have, for a long time, felt water chiller designers were trying to put too much volume past a TEC in too few passes in many cases only one pass. I think there is also some merit in guiding the coolant past in a tube/slot/hole mainly because I think it negates many of the laminer flow problems. There are some issues like oval tubing will be better than round etc but generally I think it's a better idea than putting a large flow past a copper plate with slots in and basically hoping it works.
True, as one person said sometime ago, you only cool less than a "coke" can full of coolant at a time but at least it is being cooled instead of shimmying past the slots on the easiest path and avoiding most of the cooling.
Commercial industrial TEC water chillers rely on multiple passes on the TECs and irrespective of high/low flow pumps I think this is the best way froward.
There have a couple of designs on here recently "ultrasonic2" is the best to date and actually finished but he also had laminer flow problems. "coity" and "snake" have been on here recently but have "gone cold" for one reason or another and I too am working on the principal.
Unfortunately I have spent several months hunting for a "friendly" engineer, metalworker to help me but despite offering good money it appears there are no "friendly" engineers in the UK...I wouldn't be surprised if they are all best buddies with the HVAC engineers in the UK...that's why there aren't many "friendly" ones of those either !!!
Anyhow I have managed to get the engineer inside of me to get his overalls on and despite not having done any metalwork/engineering of any sort (I am a printer/machine op) for over 20 years I am hoping to get things moving shortly. Just hoping I am not biting off more than I can chew.
Quote:
Originally Posted by zipdogso
LOLOLOLOLOLOLOLOLOLOLOLOL
Actually it's not finished but it is working. It never will be "Finished". i really want to make another one now with what i've learnt
It is my most successful TEC Project so far though
Yeah Ok...LOL it was the certainly the MOST finished.... and pretty good results by all accounts.Quote:
Originally Posted by Ultrasonic2
Quote:
Originally Posted by ilkkahy
A block like this will never perform that great or cool better than a decent chiller. but it should reduce CPU temps a little.
One of the issues with a chiller is that it cools the water not the CPU this means the water has to go through a Water block . This water block as a C/W and therefore CPU temps end up being much higher than water temps.
A design like yours reduces this issue as it's cooling the same block of copper that is touching the CPU
The problem is that it can't go much below ambient because then the water flowing through the block will take the cold water away to be heated back up to ambient.
So the idea is limited in it's maximum performance. But should be able to reduce your CPU a few C
Thanks man. i should be happy with it but im not. I've run out of money for now :rolleyes:Quote:
Originally Posted by zipdogso
These are hot and cold side temps (c) after running 100% for some time. Ambients are 21c (Q6600 @3600)
http://www.overclock.net/attachment....1&d=1236992195
I have pretty abandoned the idea of direct die cooling but I think this principal will work well in a TEC water chiller...and as TDP's go ever higher chillers might be the only option soon.Quote:
Originally Posted by Ultrasonic2
i actually think chillers have been the only option for quads for sometime now.Quote:
Originally Posted by zipdogso
So what are you working on then ?