Heater Core under ground in cement?

I have my computer in the basement of the house. My basement is redone... it's like my room all my stuff is down here. There is a 2 foot separation between the wall of my basement and the actual part of the house which contains the electrical box and a wires running across. Below is a pic so you can get an idea of what I'm trying to say: (click on it for a bigger pic)



Now behind the wall the wall is concrete floor. I want to break it a little place a heater core like a 77 bonneville and cover it up with cement. It will provide a cool surrounding which will keep the water cool NOT cold. At least a better temp than sitting in the room, right?

Then I'll pass the tude through the wall to my comp which is not never far. What do you think about this? I will pick up a electric temp reader tomorrow so I can actually see what temp the ground is. I know I need a good pump so forget about the pump. What other problems is there with this?

Will it get cold enough to cause condisation which I doubt. What about in the winter time. Has anyone tried this? Comments/suggestions please...

I'm not too familiar with the thermal properties of concrete.

I am thinking that its(concrete) not a great conductor, which would result in pretty low initial temps(assuming your basement is stereotypical, ie. remains cool), and increased time until equilibrium, but once equilibrium is reached, your performance would be subpar due to the inability of the concrete to disipate the heat.

Of course, if I'm wrong about concretes conductivity, or its conductivity is just good enough to take care of this heat, then the shear size of the concrete mass may be sufficient for some good temps.

Here is an example but this guy just placed it on the floor of his garage instead of underground.

Overclockers.com: PC Water Cooling with a Passive Radiator

Link 1

According to this table, concrete has ~2x the thermal conductivity as water, ~2x the density, and just under ~1/2 the volumetric heat capacity.

Link 2 shows a thermal conductivity of ~4/3 that of water.

I suspect the variation is due to specific properties of the concrete used.

Can't vouch for either site's authenticity though.

Problem is, the best way to dissipate heat at a constant rate is to keep all fluids (inside and outside the core) moving. If you have the radiator immersed in solid cement, the cement immediately outside the core will warm up quickly, and will only slowly dissipate the heat to the surrounding cement.

Why won't it work? The same reason a large copper cube won't work to cool off a CPU. The heat has to go somewhere after it leaves the heat source, and concrete simply isn't conductive enough to carry it away fast enough for the surface area of the floor to dissipate it.

Concrete would eat up the core in a short time. If you ever go near a construction site and watch how they pass copper pipe through a concrete slab. It has to be wrapped with foam and then taped. The concrete is caustic to the copper and it expands/contracts with thermal changes. If you wish to try this project I would suggest going below the concrete into the dirt. I would think if you are already in a basement that the temp of the dirt year round is probably 60 degrees or less.

How thick is the concrete from the ground?

Here is an example but this guy just placed it on the floor of his garage instead of underground.

Overclockers.com: PC Water Cooling with a Passive Radiator

Click to expand...

I believe the article is about a really large volume passive air system. He's relying on airflow across the garage floor to cool the water in the copper pipe.

The setup you describe would have a much smaller volume of water cooled by conducting heat into static concrete. For this to work you’d want LOTS of surface area with the concrete.

Nice article though.

What if I increase the surface area by adding more copper tube or an additional core and place it about 3 feet underground in the dirt? The place where this will be dug up is right next to the front of the house which is pretty cool and in the winter time it's cold.

Even tho the dirt or concrete cannot disipitate the heat AS FAST won't it still do a better job than being in a hot room? What about adding 2 cores a foot or so apart so the warm water from the CPU enters first core than enters second core and comes back to the computer.

Underground

nissmo300 said:

What if I increase the surface area by adding more copper tube or an additional core and place it about 3 feet underground in the dirt? The place where this will be dug up is right next to the front of the house which is pretty cool and in the winter time it's cold.

Even tho the dirt or concrete cannot disipitate the heat AS FAST won't it still do a better job than being in a hot room? What about adding 2 cores a foot or so apart so the warm water from the CPU enters first core than enters second core and comes back to the computer.

Click to expand...

I dont think you really want to use a core. Cores are designed for air flow. What you are after is something with alot of direct contact with the earth. Just use copper tubing and make a loop. I saw one setup where a guy made a grid and laid it on the concrete in his garage floor. Worked weill for him, but he obviously lived somewhere cooler than where I live. My garage floor gets hot in the summer. The more direct contact you have with the cool earth the better. Not knowing where you live, I would just make sure I stayed below the frost line that way freezing would never be an issue. Geothermal wells for cooling high end homes use this same principal. Lots of buried tubing with water flowing through it.

I'd go with buried copper pipe in long loops since more earth area means more cooling just like more airflow means more cooling in traditional systems. I don't think burying a radiator is going to get you much since the rad will end up trying to cool the water using just a small volume of earth. Past a certain point ( I want to say 36" ? probably depends on location ) the ground will be the same temperature year round, usually around 50 - 60f, so it's certainly possible to cool this way with enough pipe.

I have been thinking about similar ideas for quite a while, but burying a heater core, as mentioned by others, will NOT do the trick.

They rely on the airflow for performance.
To prove that, turn your radiator fans OFF and watch your cpu temp climb.
(NOTE! Do this at your own risk!!! You WILL have time to restart the fans or shut the pc off, but cpu temp will climb pretty rapidly.)

I have been considering putting a copper ground loop in outside my cellar computer room using a few hundred feet of copper tube- less would be required for more normal situations, but if I do this it will be to cool off 5 or 6 water cooled machines.

Corrosion is something that I have not considered or investigated yet either.......

To prove that, turn your radiator fans OFF and watch your cpu temp climb.

Click to expand...

I did that a while back, and my temps stablized just under 50C. Which is still 5c lower than the default HSF.

Note: my temp postings are only for relative comparison. CPU Diode + MBM5.

I'm doing something similar just now. I'm converting a summer cabin to be my house, and I'm then tearing up floors to have concrete/tile floor. So, I'll have one cooling loop for my server and RAID, using 10meters of 22mm copper tubing put on the ground, with gravel around it and concrete on top. The actual floor (styrofoam, concrete, floorheating and tiles) will be on top of that again. So the copper tubes are about 50cm under floor level.

The second loop will cool my main machine, and help to keep my crawlspace frost free. Not sure about what length of tubing to use though. it will be suspended from the floor above, so copper->air. Thinking about 30m of tubing should work ok..