Another shot at an Airtight PC

[RFontana]

Hi!

Being very annoyed for some time with the noise (especially pump and coil whine) and vibration on my pc and now inspired by a project by Matt from DIY Perks ( https://www.youtube.com/watch?v=QaoFh1DH51U ) I'm once again contemplating the idea of an airtight PC ahead of my long overdue planned Ryzen 3000 upgrade.

I actually had something similar (functionally. Obviously nothing so fashionable) in mind.

 

The dude is a very skilled and creative builder, but not really a pc guy per se.

The biggest problem, as always, is finding a way to remove the passive heat from inside the case.

In the video linked above, he tackles the problem by placing an extra radiator and respective fans inside the case to circulate air and send some of the heat to the outside.

My question for the well versed in thermodynamics is: WOULD THAT BE ENOUGH???

I'm not really considering making the case itself into some kind of radiator to get rid of the internal head because it would add too much in terms of complexity and cost to the build and I'm poor af.

 

If so, I was thinking of even going old school with a car radiator on the floor or on the side of my desk since it's not so expensive and it's so overkill it would probably run passive most of the time.

[LukeLinusFanFic]

It really depends on what you have inside your PC. Frankly, I'd suggest getting headphones or putting the PC in a different room before going into crazy experiments.

[RFontana]

15 minutes ago, LukeLinusFanFic said:

It really depends on what you have inside your PC. Frankly, I'd suggest getting headphones or putting the PC in a different room before going into crazy experiments.

Out of the question. I want the PC near, since it's basically the only decor in the room. And I want to use my speakers unless I'm gaming multiplayer. And I like woodwork/fabbing and would welcome the challenge.

[RFontana]

up?

[For Science!]

On 6/13/2019 at 3:40 PM, RFontana said:

My question for the well versed in thermodynamics is: WOULD THAT BE ENOUGH???

Please re-phrase the question. Using water to move heat away from the components is indeed the basic principle of "watercooling" but as you correctly identify, what actually removes the heat from the system is still air passing over a radiator. Watercooling is still aircooling.

 

If all heavy heat generating components have a means of dissipating their heat to their outside, there is no concern of overheating. This will of course depend on the components themselves, the surface area available to dissipate the heat to outside the enclosure, and the ambient temperature.

[RFontana]

 

17 hours ago, For Science! said:

Please re-phrase the question.

What I'm interested in knowing is if the radiator inside the case (remember, the case would be airtight) would be capable of taming the passive heat building up inside the case, since eventually the temp inside the case would be higher than the water temp.

So basically the radiator trapped inside the case would actually be being cooled by the water that would be cooled by the external radiator(s). And so, it would help carry the passive heat trapped inside the airtight case to the outside.

Got it? Sorry if I'm still not making much sense. English is not my native language. Maybe watch the video around the 13min mark to better understand what I'm trying to say.

Thanks

[RFontana]

up?

[SolarNova]

Easiest method, though could be somewhat expensive depending on availability of specific models of what im about to suggest, is...

 

Go further than just water cooling using radiators. Buy a chiller, place it in another room.. or loft/attic .. or basement.. run tubing from the chiller to your PC. Don't use radiators outside the case, just the chiller. On the inside use a single 120mm rad to help circulate internal air using the chilled liquid to keep temps under control. And ofc make sure to use a very quiet fan on that rad, like a NF-A12x25.

 

No noise in the room your in, and supreme cooling capacity. You can go sub ambient if you wish.

 

Added bonus of an airtight case, if you so wish, dry the air inside the case or replace it with a dry gas like nitrogen and then go very sub ambient or even subzero.

 

A airtight case open your options up to ' long duration extreme cooling'.

 

Alternatively if you just want to water cool the 'normal way', then do the same thing in terms of placement. Put the rads in another room,, or even mount them outside the house, run tubes to the PC.

[Psykocys]

Could also try to do mineral oil. 

 

As far  as i understand if you were to  have an airtight case the heat build up inside it would be large especially with mid to higher end specs. Even if you were able to get the heat away  from your cpu and gpu there is  no passive cooling for the VRMS or Mosfets and any other tiny components on  the motherboard, also usually your power supply  needs access to fresh air if would not like being in an increasingly hot airtight case.

 

Not the most well versed in thermodynamics, but i wanted to weigh in anyway

[Pyr0monk3y]

This would work, but you would need very large radiators and fans on both ends.  The issue here is that you are dealing with an air to water heat exchanger on both ends.  Air has a lot less heat capacity than water so in order to turn 60C water into 40C water, you need to move a lot of air through the fins of your radiator.  To turn 40C water into 20C water, you need even more air flow.  

 

It's definitely possible with big enough fans and radiators, but if the goal is silence then then massive amount of airflow needed defeats the purpose.

 

Also remember that this needs to be a separate loop, meaning an additional pump and additional lines need to exit the case in an airtight manor.  

[RFontana]

23 hours ago, Pyr0monk3y said:

This would work, but you would need very large radiators and fans on both ends.  The issue here is that you are dealing with an air to water heat exchanger on both ends.  Air has a lot less heat capacity than water so in order to turn 60C water into 40C water, you need to move a lot of air through the fins of your radiator.  To turn 40C water into 20C water, you need even more air flow.  

 

 It's definitely possible with big enough fans and radiators, but if the goal is silence then then massive amount of airflow needed defeats the purpose.

 

Also remember that this needs to be a separate loop, meaning an additional pump and additional lines need to exit the case in an airtight manor.  

The rad ouside the box wouldnt have much work to do IMO.

 

What I'm really trying to say, as showed in the picture attached, is that the rad inside the box would actually be like a waterblock for the air inside. Its function wouldn't be taking the heat out of the components, but rather absorb the heat from the air inside the box.

 

Edit: Now that I think of it, since the fins of the internal rad would be somewhat cooler than the air around, maybe there would be condensation on it...

Edited June 18, 2019 by RFontana
Add info

[Pyr0monk3y]

21 minutes ago, RFontana said:

The rad ouside the box wouldnt have much work to do IMO.

 

What I'm really trying to say, as showed in the picture attached, is that the rad inside the box would actually be like a waterblock for the air inside. Its function wouldn't be taking the heat out of the components, but rather absorb the heat from the air inside the box.

 

Edit: Now that I think of it, since the fins of the internal rad would be somewhat cooler than the air around, maybe there would be condensation on it...

There will not be condensation unless the fins are at a temperature below the dew point.  In your scenario, the absolute best case scenario is that the fins get to the external room temp, which will not be below the dew point.

 

Also, if your are going to actually try this, you will be much better off using a separate loop for cooling the case.  The output of the external radiator will still likely be above ambient and you need every advantage you can get. 

[For Science!]

1 hour ago, RFontana said:

 

This most definitely will not work. Watercooling loops have a equalized temperature throughout the loop due to the rapidly flowing water through the system, the entirely of the loop heats up and cools down as a whole, there are no hot and cool spots. Therefore having a passive radiator in the case serves no purpose beyond dissipating some of the coolant heat back into the sealed case. Since there is a heat generating component inside this enclosure, you are just contributing more towards a run-away thermal situation. Even if you put a fan on the radiator inside the case the delta between the heat soaked internals and the radiator temp is probably not significant enough to cool the entirety of the chassis down. Obviously at this point you're better off having an actual intake and exhaust which will actually be ambient (As opposed to liquid temp).

 

Alternatively put a waterblock on every heat generating component that needs cooling in a closed off situation (my guess: everything except for SSDs, RAM, maybe PSU?) and then have an external radiator or a heat exchanger. Basically the same idea, but just to minimize any passive dissipation within the case itself.

[RFontana]

The rad inside the case wouldnt run passive. It could probably run full blast in fact. The outside rad COULD run passive under certain temps. Since the temperature of the water (and by extension, the fins of the internal rad) would be lower than the air inside the case, the internal rad would cool the air inside as it circulates it.

[For Science!]

59 minutes ago, RFontana said:

The rad inside the case wouldnt run passive. It could probably run full blast in fact. The outside rad COULD run passive under certain temps. Since the temperature of the water (and by extension, the fins of the internal rad) would be lower than the air inside the case, the internal rad would cool the air inside as it circulates it.

But if you have a radiator with rads running full blast, this will not be silent, and defeats the original question you posed. Then it would be better to have inlets and outlets with gentle and quiet airflow while providing adequate cooling at a low noise output.

[ShadowChaser]

Having a radiator within the sealed case would do nothing towards bettering your cooling situation, but only delay the inevitable by adding extra thermal mass. Like pletny of people have said above, if you want silence, move the noise generating components away. What I would do given a sealed box with a PC in it is turn it into a liquid cooled peltier chiller and put the pump and rads far away. If the box was indeed sealed (and this point has been addressed) a pure inert gas would prevent condensation and you can run subambient no problem.

The premise that having a rad inside the box would help overall temps is a logical fallacy. Water loops don't work that way, unfortunately, unless the flow was incredibly slow or there was an extreme amount of thermal transfer, both scenarios being unlikely in this situation.

[Froody129]

I would put the PC in a sealed box, then run tunes to a radiator somewhere where you won't hear it. You'll need a crap ton of waterblock coverage though. If it's really airtight even lesser amounts of heat will heat the enclosure up quickly. If you really want it to be airtight it's going to be expensive. 

 

You could just put it in a baffled box (inside turns around and is sound dampened) which should achieve basically the same thing without the problems. In this case I would have a nice big case with water cooling with a lot of rad space, with big, slow fans. You'll likely want an intake and exhaust flow for the box, and you may also need fans for box intake and exhaust if it's very heavily soundproofed, and the passageway turns around. 

 

I didn't watch the linked video so idk if this was mentioned anywhere 

[RFontana]

On 6/23/2019 at 1:13 PM, ShadowChaser said:

The premise that having a rad inside the box would help overall temps is a logical fallacy. Water loops don't work that way, unfortunately, unless the flow was incredibly slow or there was an extreme amount of thermal transfer, both scenarios being unlikely in this situation.

The job of the internal rad wouldnt be to cool the liquid or the components. That would be the external rad's job. The internal rad would only work to lower the temp of the air inside the case a bit, since the liquid temp would be a little lower than the air inside.

 

^This^ is what I want to know better before I put effort into it. I know it's not efficient as something like a peltier or even making the back of the case into an aluminum plate with some fins or something, but working with aluminum is harder (for me) and more expensive than mdf. And peltiers spend an awful lot of power, which is not cheap here. I don't want to move anything to another room, and I don't want to double the power consumption of the pc with a peltier.

 

On 6/21/2019 at 10:56 PM, For Science! said:

But if you have a radiator with rads running full blast, this will not be silent

the rad running full speed inside the case would push next to nothing of its noise to the ouside since the case would be sealed. The little noise from the rad ouside the case I can totally live with since it would be just airflow noise, and little at that. The main goal of the rest of the pc being sealed is to avoid dust (I'm currently having to clean my pc once a month, the front mesh/filter twice that), and to prevent coil whine which drives me crazy