Using a car radiator for passive cooling?

[Supfisho]

Hello there! So I have a custom loop for my cpu(gup comming). I have been looking into passive cooling lately and I got this image in my head of using a car radiator. What i am thinking is to build a frame withaluminium profiles and attach the car radiator, some kind of a resorvir and a pump. From the frame i am thinking about running softube into quick connectors on the back of my pc and have minimal tubing inside my case. What do you guys think? Is it so crazy that it can work? Anyone tried something similar? I really want input

 

[WALL-E]

Hello there! So I have a custom loop for my cpu(gup comming). I have been looking into passive cooling lately and I got this image in my head of using a car radiator. What i am thinking is to build a frame withaluminium profiles and attach the car radiator, some kind of a resorvir and a pump. From the frame i am thinking about running softube into quick connectors on the back of my pc and have minimal tubing inside my case. What do you guys think? Is it so crazy that it can work? Anyone tried something similar? I really want input

I strongly suspect that an automotive radiator, if positioned outside the case, would be able to cool whatever computer hardware you connect to it without a fan. You are going to have to adapt your small computer fittings to an inlet that will be somewhere around 2 inches diameter. It will also probably be as ugly as sin. I am working on an internally-mounted motorcycle radiator pc now. The other forumers have pointed out to me that modern, purpose-made computer radiators are very effective, cost-efficient, and less of a headache.

 

[Zerileous]

Hopefully you're not planning to use a single PC grade pump for this.

Car radiators have a lot of fin density and will absorb a lot of heat for sure, they are meant to work their best with 40+ mph airflow however. Of course they are also dealing with a much higher capacity of heat, but there is a possibility the radiator would saturate over many hours of load and at some point suffer in a passive setup.

 

[Supfisho]

Hopefully you're not planning to use a single PC grade pump for this.

Car radiators have a lot of fin density and will absorb a lot of heat for sure, they are meant to work their best with 40+ mph airflow however. Of course they are also dealing with a much higher capacity of heat, but there is a possibility the radiator would saturate over many hours of load and at some point suffer in a passive setup.

Thanks for the input! I am not going to use a standar pc pump, need something stronger don't know what kind yet.

 

[WALL-E]

Alright, so Im bored and sitting at work at my essential job, so I pulled up info on automotive pumps.

A belt-driven pump in a 3.8L car uses a maximum of about 200w, operates at a maximum pressure of half a bar (7 psi), and has a maximum flow rate of 20 gallons per minute (at 0 psi). A car cooling system operates at 100C (much hotter than your PC liquid should be) and cools at least two orders of magnitude more heat than a pc. Assuming 20% of engine heat goes into the engine block (most goes into the exhaust gas) and an engine is 30% efficient, a car making a constant 100 horsepower (a brick-shaped Buick highway cruising at 3000 RPM) will dissipate 50 kw through the radiator, which is the equivalent of about 100 high-end, overclocked SLI computers running at load (pulling 650 watts from the wall).

I almost feel like a regular D5 pump would get the job done flowing a max 1.5g per minute max (at 0 psi). This is just a guess, since its a comparison of apples to oranges. A car radiator cools at least 100 times the wattage of a PC, operates at least 40C hotter (which is significant since cooling rate is directly proportional to the temperature gradient), has massive airflow, and has a pump flowing 10 times as much liquid.

For something closer to an automotive pump, you could try a spa pump. Laing makes these, and many operate around 60-90 watts. To reduce the load on your PSU, you could get an AC pump. For a fun project, you could wire its power cables into the AC input on your psu, and connect it to like a 5v relay which you would connect to your molex power connector. This way the pump would turn on when you turn on the computer, but wouldn't pull any power from your PSU.

Please send me pics if you build this abomination of a PC!

 

[Supfisho]

Alright, so Im bored and sitting at work at my essential job, so I pulled up info on automotive pumps.

A belt-driven pump in a 3.8L car uses a maximum of about 200w, operates at a maximum pressure of half a bar (7 psi), and has a maximum flow rate of 20 gallons per minute (at 0 psi). A car cooling system operates at 100C (much hotter than your PC liquid should be) and cools at least two orders of magnitude more heat than a pc. Assuming 20% of engine heat goes into the engine block (most goes into the exhaust gas) and an engine is 30% efficient, a car making a constant 100 horsepower (a brick-shaped Buick highway cruising at 3000 RPM) will dissipate 50 kw through the radiator, which is the equivalent of about 100 high-end, overclocked SLI computers running at load (pulling 650 watts from the wall).

I almost feel like a regular D5 pump would get the job done flowing a max 1.5g per minute max (at 0 psi). This is just a guess, since its a comparison of apples to oranges. A car radiator cools at least 100 times the wattage of a PC, operates at least 40C hotter (which is significant since cooling rate is directly proportional to the temperature gradient), has massive airflow, and has a pump flowing 10 times as much liquid.

For something closer to an automotive pump, you could try a spa pump. Laing makes these, and many operate around 60-90 watts. To reduce the load on your PSU, you could get an AC pump. For a fun project, you could wire its power cables into the AC input on your psu, and connect it to like a 5v relay which you would connect to your molex power connector. This way the pump would turn on when you turn on the computer, but wouldn't pull any power from your PSU.

Please send me pics if you build this abomination of a PC!

Thank you so much for the info! Ofc if i manage to get this built I will post a Build Log! I will try a D5 at first, then go over to something bigger :-D

 

[don256us]

In the old days before pre-built cooling loops, guys had done this. Aquarium pumps and fountain pumps work great and run from the wall outlet. Easy peasy. You just want to get a pump with a higher value for "head" which will give you an idea of how much power it has in addition to flow rate. Back in the day, I had used a heater core from a car as my radiator. I went to the junkyard and asked for a heater core. They asked what make and model I need and my answer was that I didn't care. I was more concerned for the layout of the radiator. They of course asked what I was doing with it and when I told them it was for my computer, they cursed me out... for a while then got to showing me all of the cores that they had pulled. I ended up with a '74 Vega heater core. Worked great too.

 

[Sam__]

In the old days before pre-built cooling loops, guys had done this. Aquarium pumps and fountain pumps work great and run from the wall outlet. Easy peasy. You just want to get a pump with a higher value for "head" which will give you an idea of how much power it has in addition to flow rate. Back in the day, I had used a heater core from a car as my radiator. I went to the junkyard and asked for a heater core. They asked what make and model I need and my answer was that I didn't care. I was more concerned for the layout of the radiator. They of course asked what I was doing with it and when I told them it was for my computer, they cursed me out... for a while then got to showing me all of the cores that they had pulled. I ended up with a '74 Vega heater core. Worked great too.

As Don said. It's been done many times. A quick google should pull up a few pictures from a decade or so ago when there were less watercooling parts available than there are now.

It's very doable if you can convert the pipe diameters, no too difficult. Again, the pump head pressure is key for it to be able to get the water around the loop.

And for the love of god, pump a LOT of water through (I'm talking hours or days left pumping) it to clean it out before you put it anywhere near a water block. Try hot water, cold water. Shake it around. You need to displace all the possible contaminants in the radiator. Anything left in there will happily collect in the fins of the CPU/GPU block and effect performance.

 

[Aleslammer]

Car rads are interesting and work, heater cores are better. Single pass and side flow not a big deal with the pump used water still moves down hill, so flow design within the rad should be considered. Biggest problem would be where the channels in the rad can pass more water than what can be pushed through the most restrictive point in the loop. Water takes the path of least resistance so in a single pass top res rad with inlet and outlet on the same side, if only half the channels are needed to pass the flow those channels closes to the outlet/inlet will be what gets used.

 

[caddi daddi]

For our use look at an a/c condenser, at our flow rates it might be A little better.
Either way chuck it out the window in the winter.