Senior Project Design (active submersion / Internal cooling device)

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ShinySwords

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Hey guys im new to the forum but ive been readin alot everyday and this place is great, especially in resaerch and development of my senior project for Alfred State College.

I would like some help at this one, I have passed and been accept to go ahead with my senior project, formally named Commercial Super Cooling. Any help will be greatly appreciated.

I am going to create my own case to hold the main parts of the computer, this case will be sealed and have complete liquid submersion, along with a miniture cooling device inside the case, which will cool the liquid to a low temp, and a few slow moving fans to circulate the liquid.

A few questions come to mind after a few days of research, and im sure more will come the further i get into this, but here are a few basic ones:
1. What should i make the case from?
2. A few ideas on cost and effectiveness of the different liquids to use?
3. What components on the computer can be submerged? (EX. boards, drives)
4. Anyone know of a few cheap freezing units that are low on size and work to cool small areas to low temps?

As I said im sure there will be more questions as I go
Thanks for your time
Daniel Raatz
Alfred State College Student
Custom Made:
AMD 2600+, 512 RAM, GeForce 5600 w/expanded memery, 3 harddrives, DVD/CDRW, and yes 10 (80mm) case fans - all light blue n red
 
heh...I'm fairly certain I can answer your questions.

First see my Thinktank post.
The worklog is here

Discussion on fluids here

You have taken on quite a project.Mine took about 1000 hours.
Good luck !

:D
 
I think your project is awesome, beyond belief. I hope that mine can be close to yours, it would blow the professors out of the water, I will take your design into consideration heavily while creating this, I will be very appreciative of your help in this matter, also do you have any tips on how to show the advantages to this machine submersion compared to a normal air cooled machine in a way that’s easily understood? Also did you include the freezing unit into this machine?

Thanks Dan
 
a few comments from the peanut gallery:
use submersible pumps for circulation. they are made to work with viscous fluids, unlike fans. more likely than not, a fan put into a high-resistance medium will just burn out after a little while. you might be able to scavenge some suitable aquarium pumps from people you know who once had fish, and gave up on them.

you probably need a heatsink on the proc even when submerged. just make sure that it has WIDE fin spacings. you might actually be okay without a sink, however it would probably be safest to try with a sink on there, and a pump directing a stream of coolant at the proc, and then back things off from there, if it seems that your temps are low enough to try for direct-die.

as for what can't be submersed: anything with moving parts, like all of your drives. the PSU might or might not be submersable, depending on what fluid you end up using. as for the rest of it......anything that doesn't have moving parts should be fair game.

both BrainEater and myself use peltier coolers to get sub-ambient. they work, and they don't require as much tooling as phase change, however they are power hungry, and you need the supplies to run them. brain eater's think tank draws, what, 1 KW out of the wall to get around 850W of theoretical pumping capacity? i'm running 226 watts to chill my CPU alone. the pelts are cheap, the PSU isn't.

if you DO decide to go for pelts, you should probably make sure to have more than twice your expected heat load, in terms of what the pelts are sold as. they only pump that much heat with both sides at room temperature, which you will never have, and the cool side temps that they are able to generate go down as you put more load on them. running a pelt at half it's rated capacity, you might be able to keep temps 30C below the hot side temperature.

again, if you decide to chill with pelts, you need some way of effectively dealing with the combined waste heat and pumped heat. if you are letting the pelt hot sides get up to 50C, and chilling down the cold side to 20 C, that doesn't exactly put you ahead of room temperature air cooling.

more that i could say on the subject of pelts, however i don't know if you are set up to build or buy a phase change pump. if you are, that is almost certainly the better option.
 
how much and where could i get a good phase change pump, i have a fair amount of finacing that i can sink into this but as I am a college student ill probally be limited to a total of about 1000, give or take a few hundred, for the setup, not including the computer parts, i got them lol.
 
ShinySwords said:
also do you have any tips on how to show the advantages to this machine submersion compared to a normal air cooled machine in a way that’s easily understood?
Click to expand...

Advantages over air cooling? I really don't think there are any ..heheh : It's heavy ,expensive and difficult to build,really expensive to run and inefficient at cooling.

It just looks really nice. :cool:

On a serious note tho , The only advantages I can think of would be a) it cools every component evenly , and b) it is pretty much insensitive to thermal variance.
 
one of the few ways to make a case for chille fluid immersion, is that it helps to eliminate any potential condensation problems.

normally, when you go sub-ambient, you have to insulate and waterproof to guard agains condensation forming on your electronics, and shorting things out. with immersion, that's not as much of a worry.
 
Shiny, as DFI have mentioned, most of time people submerge to avoid condensation issue when going below ambient temperature. Recently, I've seen some projects where they cool CPU well below typical single stage (like -100c) using cascade cooling and cooling GPU, etc and submerge it into this type of liquid bath to prevent condensation... few even trying to cool submerged liquid to cool all the components well below ambient. (only issue would be at certain temperature below zero, some components in mobo such as capacitors starts working)
These are truely extreme measures I've seen and interesting project.
There are few people around who can build such single stage unit. I can build one myself too but you will have to be more specific on what kind of total heat output you are looking to cool, what temp you are expecting (liquid temp), thermal conductive property of such liquid, etc. Now, if it is direct die (meaning only thing getting cooled by such unit is CPU), it does simplify a little and you can look for used unit (mach, vapochill, etc) or get custom one built per your specification.
Think throughly on what you want to do, what you want to achieve and what you think you can deal with on noise/power draw, etc.
 
I wanted to build a tradiional peltier/waterblock system and just keep it submerged to prevent condensation. Due to money issues, the project's on hold for now. If you did it that way, you don't have to worry about your immersion fluid having to absorb and dissapate the vast marjority of the heat. Then keeping the fluid "stirred-up" isn't as important.
 
Mark305TBI said:
I wanted to build a tradiional peltier/waterblock system and just keep it submerged to prevent condensation. Due to money issues, the project's on hold for now. If you did it that way, you don't have to worry about your immersion fluid having to absorb and dissapate the vast marjority of the heat. Then keeping the fluid "stirred-up" isn't as important.
Click to expand...
it's MUCH easier to waterproof your PCBs, insulate reasonably, and have done with it.

http://www.swiftnets.com/products/h20-120-T.asp

add another rad to this kit and have done with it.
 
Nice project... answers in line:
ShinySwords said:
1. What should i make the case from?
I recommend Styrofoam, like a cheap-arse 'cooler' that you take camping in order to keep beers cold! :)
2. A few ideas on cost and effectiveness of the different liquids to use?
Whatever you end up using, make sure that it does not conduct :) I heard mineral oil is an option
3. What components on the computer can be submerged? (EX. boards, drives)
Don't submerge drives, I really don't think they'd like it.
4. Anyone know of a few cheap freezing units that are low on size and work to cool small areas to low temps?
Maybe a used AC?!
Click to expand...


 
Mark305TBI said:
But that's not nearly as fun!
Click to expand...
i sometimes feel like my head is giong to explode when i read thigns like this................

pain in the ass to build and maintain != fun.
 
DFI Daishi said:
i sometimes feel like my head is giong to explode when i read thigns like this................

pain in the ass to build and maintain != fun.
Click to expand...
Don't you ever want to do something 'cause it's new and challenging? That's why I built my watercooled rig, when air cooled would have been plenty sufficient. Putting them together and testing 'em out is just as fun to me as actually using it. If I had the money, I'd be building new ones all the time.

The geek wow factor of immersion is beats out insulation all day long, too.
 
Mark305TBI said:
Don't you ever want to do something 'cause it's new and challenging?
Click to expand...
no. no, i don't.

i moved up to TEC from an SP-97 with delta 92mm EHE. i went TEC instead of straight water, because i was unwilling to shell out the kind of money that watercooling costs, for no performance gain. for me, the cooling is about performance first, last and always. i would have used phase change instead of TEC, if there was a CPU and GPU cooling solution of that sort that is in the same price range.

TEC has ended up costing me quite a bit in terms of ruined hardware, so looking back now, i think that i should have gotten top-flight water instead. the point remains, i didn't do it, and i don't do it, for the challenge or the acclaim. i do it to run my games faster, smoother, and prettier.
 
Ok before i get too far ahead of myself the first thing at hand is the case. Should i try and make one or buy one and customize/seal it, and if i should buy one, anyone have any really good suggestions that would be visually appealing and effective. Also I got to thinking and I believe that I will need to cord out the connections from the motherboard up and out of the liquid, maybe the top of the case. And lastly I think i might have to have a way of seperating the liquid submesion part from another part that will hold the drives.

BASIC QUESTION HERE: What do i need for a case to make this monster, that would be effective and practicle for everyday use
 
ShinySwords said:
Ok before i get too far ahead of myself the first thing at hand is the case. Should i try and make one or buy one and customize/seal it, and if i should buy one, anyone have any really good suggestions that would be visually appealing and effective. Also I got to thinking and I believe that I will need to cord out the connections from the motherboard up and out of the liquid, maybe the top of the case. And lastly I think i might have to have a way of seperating the liquid submesion part from another part that will hold the drives.

BASIC QUESTION HERE: What do i need for a case to make this monster, that would be effective and practicle for everyday use
Click to expand...
You could do an aluminum one and weld it up.... but you would prob be better off finding a serviver type tower that you can seal.... GL.....
 
Hey i was seaching for the phasechange pumps and i dont think that spending like 900 on one part would be practicle, however, i did find the mini vapochill unit that attaches to the processor, but im not sure how it would work in a submesion, check it out and tell me what you think http://www.frozencpu.com/ex-blc-212.html

I would also like to thank all of you for your help, your all awsome
 
ShinySwords said:
Ok before i get too far ahead of myself the first thing at hand is the case. Should i try and make one or buy one and customize/seal it, and if i should buy one, anyone have any really good suggestions that would be visually appealing and effective. Also I got to thinking and I believe that I will need to cord out the connections from the motherboard up and out of the liquid, maybe the top of the case. And lastly I think i might have to have a way of seperating the liquid submesion part from another part that will hold the drives.

BASIC QUESTION HERE: What do i need for a case to make this monster, that would be effective and practicle for everyday use
Click to expand...

Some clear polycarbonate can easily get down to -40c before becoming brittle. (it is expensive though) Most do get very brittle well before that temp. Now if you are doing it purely for insulation. I can tell you it's much money wasted with no gain really and much pain added for component swap, etc.
Only reason I could see doing immersion really is to cool components in mobo and possibly GPU to certain degree. (now I am not sure how viscousity of oil will impacet GPU cooler's effectiveness)
You could make case out of above mentioned casing, Make tight seal and progress from there on.
BTW, that vapochill thing is just a heatsink like all air cooling heatsinks are. In fact, if temps start hitting say close to 0c... it will be even less effective than non heatpipe ones such as good old slk900 series, etc. It was meant to be used at ambient temp where proper evaporation happens and condensation happens. The gas used is not designed for this low temps that usually goes with submersion
 
ShinySwords said:
Hey i was seaching for the phasechange pumps and i dont think that spending like 900 on one part would be practicle, however, i did find the mini vapochill unit that attaches to the processor, but im not sure how it would work in a submesion, check it out and tell me what you think http://www.frozencpu.com/ex-blc-212.html

I would also like to thank all of you for your help, your all awsome
Click to expand...
??????
what exacly do you think that will do? it's just a normal, air cooled, heatsink.

it isn't a heat pump. it won't do anything other than move heat from the processor, into the fluid. once the heat is in the fluid, what are you going to do?

before you worry about making a pretty case for this project, you need to figure out what it is that you are doing.

at this point, are you looking at doing an ambient temperature immersion, with a rad, fans and coolant circulating pump? are you looking at doing a ambient temperature immersion, with a chilled cooling block pressed against the CPU? are you doing a chilled fluid immersion? how are you going to pump your heat, if you are still doing an active solution?

figure out what cooling technique you want to use before you worry about how it looks. i have worked with plenty of pieces of prototype hardware, and helped to develop a few items at the university, and they don't typically look like works of art.
 
I want to try to do active submersion in a chilled liquid, while minimizing cost, but not cheapin out on the constuction of it. Im thinkin after seein most that the peltiare is prolly the best to use. Im thinking that the chilled part doesnt have to be super low in temp but atleast close to freezing. I wish i could afford the phase change pump but i costs around 850, which i think is a bit much. I know it doenst have to be a work of art but it has to be practicle to the point where its is acceptable for every day use, so basically sealed and not humungous
 
hmmm, i think i might lean towards the active submersion with a simple pump to circulate the liquid, and some kind of radiator type technique with a pipe running through the liquid that is very cold (pipe cold). Combined, this would mean the pump would push the liquid toward the processor and cold pipe running through the liquid would chill the liquid. I think i might leave the heatsink on the processor to create a better surface area.

On kind of a different note, i wonder if i could mod out a mini fridge, kinda like a sealed envirorment, the fridge would ultimately insulate the computer, while at the same time cool the liquid inside, and allow you to just open (or maybe mod a window into the door) to see the computer. Im not sure if the hard drive and such could be set into a fridge. im not sure how well im trying to explain this but if ur unsure just reply and i will clarify

Last note, what about the power supply, most power supplies have fans in them, would be be possble to submerge a power supply if the fan was removed from it, or easier to just have the power supply not submerged and be seperated with the hard drives n cd roms n such
 
you could pump the fluid through a heat exchanger and phase the other end of it, that would get you much lower temperatures then a pelt could give, and you could take all the AC components out of a mini fridge or air conditioner, you would just need to change it from cooling air to cooling the heat exchanger, only thing i would be worried of is the freezing temperature of whatever fluid you use
 
Forget about the mini fridge.You'll just burn it out.

This all boils down to a simple rating of the compressor.

It's called 'duty cycle' .

Duty cycle is the percent of time the device , in this case the compressor, can run under full load , during a 10 minuite period.

Now , most fridges and freezer compressors are rated for a MAXIMUM duty cycle of 25%...This means the compressor can run for 2 mins 30 seconds at full load , then it needs to rest for 7 mins 30 secs......(to cool down)

A computer is a continuous heat load . This means you need a compressor capable of 100% duty cycle. I.E. continuously running .

-----------------------------------------------------------------------------

As far as the PSU goes : If ya look at the pics of the thinktank , you can see the PSU at the back end of the tank.It is caseless,fanless, and fully submerged.So yes , it's totally possible.However , In the thinktank rebuild , I will not be putting the PSU back into submersion . That's 300 watts of heat the coolers won't have to dissapate.

:D
 
so you would need somthing far more heavy duty then a mini fridge, what about a window unit air conditioner?
 
OK so the mini fridge is out. I do like the idea of a heat excahnge unit to cool the liquid. So any ideas on a heat exchange unit that will continually process and cool the liquid. If i could get this then it would work to cool the liquid and circulate it.
 
you can build a heat exchanger if you really wanted to, you would just need to have the air conditioners gas evacuated first and you would need to have it inspected and then charged after you finish building it, at least with my understanding of how things work for HVAC look into whats involved in building water chillers, your doing the same thing ;)
 
BrainEater said:
A computer is a continuous heat load . This means you need a compressor capable of 100% duty cycle. I.E. continuously running .
Click to expand...

Not necessarily... you could design the system so that it runs with a only 25% duty cycle but still transfers enough heat during that 25% of the time to keep the fluid temperature within some acceptable range of temperatures. This is the exact same way it works in reality, heat is constantly flowing into a fridge but it is only pumped out every so often. The inside temperature varies slightly, but not too much.
 
Ok....point taken.
However , In order to run at 25% duty cycle , the compressor will need to be able to remove about 4 times the continous heat load value during the 25% of the time that it's actually on.....
On a cost basis , it's probably cheaper to get a 100% duty cyle unit , than to buy one big enough to run at 25% duty.
 
BrainEater said:
Ok....point taken.
However , In order to run at 25% duty cycle , the compressor will need to be able to remove about 4 times the continous heat load value during the 25% of the time that it's actually on.....
On a cost basis , it's probably cheaper to get a 100% duty cyle unit , than to buy one big enough to run at 25% duty.
Click to expand...

Possibly, but until someone actually prices out parts for each system, we don't really know that :D
 
Forget mini fridge. Those usually uses fractional horespower down to 1/8th - 1/12th that is rated only good for about 200W of heat removal at 15c-20c (yes not negative but positive). Duty cycle doesn't have as much bearing on this as compressors unless they have defect or incorrectly installed can run decade for fine even in continous use.
The real problem will be since compressor is running to cool high evaporating temperature, it will have to work harder, pressure in system will be much higher than it was primarily intended for, not to mention I am absolutely sure decent system's mobo power output, memory heat output, CPU heatouput, GPU heatoutput will be in neighborhood of 250-350 watt under heavy usage.
What will really happen is that the mini-fridge will start getting overheated, too high of discharge temp might cause motor lock out and you will just keep raising the temperature. Even if motor doesn't lock out, compressor temp will get high enough that acid might form and eat through the system (cooling part) and eventually give in.
For what you propose to do, you DO need at least 1/3 hp compressor, more likely 1/2hp compressor that can cool heavy heatload with LBP/MBP configuration, with heat exchanger to cool water/oil. So not much different than waterchiller but you are circulating oil around instead. If you think $850 is too much to spend, I don't think you are quite ready to start on this kind of project.
I will tell you what I think:
1) Cooling component with 1/2hp up to heat exchanger part about $400-600 from custom builder (this is practically 1st stage of cascade) -> This is without casing.
2) Oil pump/ casing: somewhere between $200-300 as you will have to think about insulating nature of such casing as well as material.
3) Proper method of controlling this. You've got to have some way to prevent over temperature, etc: manual :$0, automated: $100-150
Than, here is interesting things you have to prepare for whenever you do something this extreme.
4) Spare parts... you WILL burn components down the road. Maybe too much voltage, maybe some simple mistakes.
And I didn't even include any shipping cost yet.
 
I am taking all post into consideration and actually the minifridge would be an easy way out but not effective or practicle. I did think of a way but i dont know if it would work, i will research it tho because it seems almost too good to be true. Freon is a chemical which gets cold but applying heat to it in a sense. If i had a couple smaller peltier devices cooling the liquid, i could at the same time use the hot side of the peltier device to apply a heat to a freon pipe or unit. In sense the peltier devive would cool the liquid and at the same time the heat produce by the hot side could be utilized to create the heat to cool the freon, which would be piped and connected to all the peltier devices and then used to cool the processor. Wish me luck on the reasearch for this...
 
ShinySwords said:
I am taking all post into consideration and actually the minifridge would be an easy way out but not effective or practicle. I did think of a way but i dont know if it would work, i will research it tho because it seems almost too good to be true. Freon is a chemical which gets cold but applying heat to it in a sense. If i had a couple smaller peltier devices cooling the liquid, i could at the same time use the hot side of the peltier device to apply a heat to a freon pipe or unit. In sense the peltier devive would cool the liquid and at the same time the heat produce by the hot side could be utilized to create the heat to cool the freon, which would be piped and connected to all the peltier devices and then used to cool the processor. Wish me luck on the reasearch for this...
Click to expand...

You're talking about cooling a peltier with a phase-change system. Freon does not get cold when you heat it, it gets cold when it changes phase from liquid to gas (as does any material in a similar situation, it's thermodynamics). In a phase change setup, the addition of heat drives the phase change. It's entirely possible to cool the hot side of a peltier with a system like that, but you still need the entire system there - freon is not going to do anything for you without a compressor, condensor, evaporator, etc...
 
Conservation of energy can't be avoided....
You CAN'T cheat into getting more energy or dissipating more energy. Period.
Before you start having this outlandish idea, here is basically how phasechange works.

1) Freon (or any refrigerant) in compressor gets compressed... you have hot & high pressureized gas.
2) It goes to condenser where pressure remains but due to condenser taking heat out using air cooling or liquid cooling. This makes this gas to become high pressurized liquid.
3) This high pressurized liquid goes into metering device. It lowers pressure of liquid. Now you have low pressure, low temperature liquid (hopefully) entering evaporator where pressure is VERY low... sometimes certain vacuum as well as having bigger space. Refrigerant with less pressure turns into gas. In this process, it takes heat away from surrounding (evap gets colder). And becomes cool gas.
4) Now gas gets back into compressor cools compressor some gets warmer and gets compressed and become hot high pressurized gas.
Cycle repeats.
Now what you are talking about using peltier to make this process just doesn't work. You also forget to think about inefficiency of peltier in it's power consumed vs heat that can be removed. (more correctly transferred)
I honestly think you need to study bit more of what others have done before jumping into this kind of experiment.
If you are talking about peltier to cool cpu but peltier's hot side getting cooled by phasechange unit... you are talking EVEN MORE heatload than originally intended by at least 30-50% more. That small fridge will never make it through first 30 minutes. In fact, if it doesn't shut down promptly, you might see something exploding off such as condenser or some coppuer tubing. (It should shut down but things sometimes aren't perfect)
 
Before i begin, i would thank you guys for all your help

How easy would it be to have a couple low power peltiers to cool the liquid, to cover more cooling surface area and then have like a radiator or somethin keepin the hot side of the peltiers atleast around room temp, and last have a pump blowing most of the cooled liquid at the processor that has a heatsink on it
 
what about these http://www.tetech.com/assys/water.shtml
i would like the biggest 200 watt one but i dont think i need that big of one to cool the like 3 gallons of liquid in the case, check it out and tell me what u think,
if this doesnt work i think ill go with a few peltiers since there cheap and seem effective for about a 50 degree temp difference
 
for the operating cost of a 200 watt peltier, as well as the $600 price tag, you are probably better off going phase for simmalar cost and lower temps(i belive a typical phase changer costs somthing like $600 to build) im probably going to be proven wrong tho, 200 watts of power consumption just for cooling sounds absurd to me tho
 
that 200 watt cooler is enough for a CPU and nothing else.

to chill fluid for the whole system, you should be looking at like 2 or three pelt chillers of that power level.

you might want to look into two waterblock-pelt-waterblock heat pump/exchanger units, with the waterblock on the hot side of the pelt being cooled by a watercooling loop, and the waterblock on the cold side chilling the immersion fluid.

alternately, this is a pre-fab unit that has substantial chilling capacity: http://www.swiftnets.com/products/MCWCHILL-452.asp

however, that would take a big bite out of your total budget, and you might need more chilling than one of these can put out, in order to cool a full computer.

maybe one of the people who are into custom phase change might be able to get you onstream with a cheap, custom, phase change chiller.
 
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