Passive Water Cooling?

[Daharen]

Okay, so I never thought this was practical... And then I saw this video:
 

There is a point in the video where he turns off the fans, while the system is under load, and the temperature STARTS to rise, but then remarkably stabilizes... Now... I am wondering if this is a fluke, if I'm just deluded, and misunderstanding what's going on here, or if indeed that is what is happening?

If it is... I have an Phantek Enthoo Series Primo Case, and I'm wondering if I could get away with passively cooling a 8700k and a 2080ti using 2 x 480mm x 60mm + 1 x 380mm x 60mm + 1 x 120mm x 60mm radiators with no fans? Obviously that's not the same as 4 480mm x 60 mm radiators, I'm essentially using 3, so a little less then what he did... But... Still I can't wonder if it might work? Does this seem crazy? Or do you think it has a chance of working?

Obviously it's not totally passive I should say, you're still running a pump... 

[dgsddfgdfhgs]

7 minutes ago, Daharen said:

Still I can't wonder if it might work? Does this seem crazy? Or do you think it has a chance of working?

all it matter is the volume of liquid in the loop.

more liquid > slower rate of temp increase.

 

[KarathKasun]

24 minutes ago, dgsddfgdfhgs said:

all it matter is the volume of liquid in the loop.

more liquid > slower rate of temp increase.

 

Also surface area.  A temperature delta between the radiator and ambient air is enough to cause airflow.  With enough surface area, this convection flow is enough to cool the loop.

 

The same applies to the water itself.  You can, in theory, make a closed loop water cooler with no pump.  A company was actually working on this type of design, but temps get pretty high.  You have to be near the boiling point of the water, which was around 80c for their setup.  The inside of the loop was under slight vacuum to reduce the boiling point of the water.

[TrigrH]

25 minutes ago, KarathKasun said:

Also surface area.  A temperature delta between the radiator and ambient air is enough to cause airflow.  With enough surface area, this convection flow is enough to cool the loop.

Exactly if the pump is strong enough to still push the liquid through all those radiators with enough surface area you can dissipate the heat without the need for fans. @Daharen

[Evolution Stu]

This theory is exactly why I built my first watercooled system back in 2008. Back then I had 3x AMD 7970 in tri-crossfire config along witha de-lidded 3770k. 

 

The noise was enough for me to not want to game at all at night, it was crazy. Those old AMD cards were crazy loud!

 

So i set about building a system with enough water that it would take a long time to saturate the loop with heat and it would in fact stay silent for a very long time. 

 

I chose a 1260 external and a 380 internal to do the job. 

 

It worked really well, with the big rad fans being virtually silent on full tilt anyway. The fans you can fit on internal radiators are far too noisy, but I had a few of them on the 380 too and they came in if the GPU out to large radiator out delta got too low and temps into rad 2 were getting a little too high. 

 

This was all set up via an aquaero pro, the aim being to keep the fans off as long as possible. 

 

Worked perfectly. If I was just browsing the web or working,  the fans NEVER came on. If gaming something light I could game for around 45 mins before they even span up slowly.

 

HWBot benching I just enabled them all with an override, because 1c matters when you are geeking... lol   

 

 

[Daharen]

9 hours ago, Evolution Stu said:

Snip...

That's awesome, I just bought all the radiators for my build. I'm going to be pairing them with some overkill but silent Noctua fans, and hopefully they'll never go past 450rpm. 

I'm also working on another project, that's really stupid, but probably needs a separate post for now... Ideally I want to keep this case, PSU, and waterloop for the foreseeable future regardless of upgrading to the latest and greatest hardware outside it as it comes and goes, so some more extreme, but also variable modifications are my target next... Namely chilling, but without running up the power bill for normal use, it turns out to be a rather complicated problem.

[Benjeh]

8 hours ago, Daharen said:

That's awesome, I just bought all the radiators for my build. I'm going to be pairing them with some overkill but silent Noctua fans, and hopefully they'll never go past 450rpm. 

I'm also working on another project, that's really stupid, but probably needs a separate post for now... Ideally I want to keep this case, PSU, and waterloop for the foreseeable future regardless of upgrading to the latest and greatest hardware outside it as it comes and goes, so some more extreme, but also variable modifications are my target next... Namely chilling, but without running up the power bill for normal use, it turns out to be a rather complicated problem.

The bigger your rad surface area, the more heat it can get rid off, your cooling will never be lower than ambient temps but the cooler your coolant, the cooler the parts the cooler the system etc etc etc. Air is constantly moving around you, just because you can't feel or see it, doesn't mean it is dead still. Also someone commented on the more coolant you have the longer it takes to heat up which is true to a degree, but it will still heat soak and equalise eventually.