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Oil-Cooling 802.11 Infrastructure
gomoX writes "A group of 802.11b fans in Tordera, Spain, are running a wireless node on the roof of a building, with the idea of a free wireless network for everyone on the neighbourhood. Its a system running linux with a home made can antenna, mounted on a plastic tool box in the roof. To keep it cool under the sun and protect it from rain, wind, they have immersed it into vegetable oil (yes, the whole thing). As oil is non-conductive, everything should run fine. The site is in Spanish, here is the google translation and the google cache."
.. I've never had deep-fried RAM before.. could be tasty.
My experience with vegetable oil is that it fries in heat...how the hell does this work?
Wouldn't vegetable oil retain heat longer than the plastic and metal that it was intended to protect? I could see this thing getting very hot on a sunny afternoon.
This is a really great idea. So far /. has only mentioned these kind of things for Europe and North Africa. I wonder if us North Americans will manage to catch up one day? ;-)
Saskboy's blog is good. 9 out of 10 dentists agree.
"That should run pretty slick!"
And a few weeks later...
"Eww, rancid!"
The biggest problem with immersion based oil cooling is that it tends to soften PCBs. I suppose that, if you never really jiggle the setup, it will pretty much remain where you leave it (especially if you keep the oil cold and viscious), but it could cause problems.
funny munging
WI-FrIed?
---- "Logoff! That cookie shit makes me nervous!" - A. Soprano
In Australia our major power supplier here does that for all of their high-tension cables that go underground - they're encased in a layer of plastic, but the rest is oil. It not only is cheaper and lighter than other sheathing forms, but it insulates and dissapates heat at the same time
The reason why they used oil is first to avoid the whole thing to get drowned. They reckon that it will avoid condensation water to fry the motherboard... How paradoxal.
It also rubs the lotion on its' skin, or it gets the hose again...please do not be pressing in the penguin, as that excites the penguin too much.
Thank you for your support.
Those people got the "fried chips" idea all wrong
Con el disco duro creíamos no había problema porque dicen que vienen "envasados al vacío" pues ahora podemos decir que no se si todos son igual pero el que usamos en primer lugar NO lo estaba. Lo metimos dentro del aceite y funciono bien, incluso dejamos todo el sistema 2 días enteros funcionando dentro del aceite sin problema alguno, el problema vino al moverlo para colocarlo en el tejado, que fue cuando posiblemente penetro aceite en el interior y una vez en el tejado no arrancaba. Entonces tuvimos que bajarlo todo de nuevo y buscar otro disco duro, instalar todo el linux de nuevo y no meterlo dentro del aceite. O sea que atención: NO hay que meter el disco duro en aceite ya que por algún lado entra dentro si lo meneas un poco
Basically, they inmersed everything in the oil, including the HDD (they didn't need a CD-ROM or FDD) and they figured the HDD would work even though it had moving parts because they're vacuum-sealed. Not so, their first prototype worked for two days and then the HDD died as oil got into the drive mechanism. They had to look for another disk, reinstall Linux and the rest of the software and then figure out a way to keep the hard disk out of the oil.
So there you have it folks, never put your hard disks in Mazola - they die.
Fans are usually removed for this sort of thing. I've seen quite a bit of this with extreme overclockers. The idea is to fill a tank, like a styrofoam cooler, with oil. Drop in a fluid pump, like one for a fish tank. Pump the non-conductive oil OUT of the container, letting it spill over the cooling unit of a stripped window air conditioner, flowing back into the cooler. You can also add a filter to the process to help keep the oil clean.
It takes care of cooling the system -- they can get down to absurd cold temperatures.
There shouldn't be enough pressure for the oil to push itself under the contacts -- unless you immerse the motherboard down a few meters or so.
Ideally, if this isn't a web server and just an AP, they don't need a hard drive. They should switch to a 512 Mb compact flash drive or something with no moving parts.
Learning HOW to think is more important than learning WHAT to think.
I hear that in oil immersion based cooling the oil tends to seep in and interrupt any less than perfect soldering connections, causing mysterious errors.
Any word on this?
It's Christmas everyday with BitTorrent.
They'd better hope that no one posts a link to their server or the whole town will be able to cook their fries in it too...
Have you seen my stapler?
Wow... this is a phenominally bad idea for several reasons... I think they were just doing this for the coolness factor (ha ha ha).
First off, we're using wires to transmit our signals in the first place,so instead of immersing the whole fixture in oil, you ought to run wires up to the rooftops and have all of the computer equipment in the house, in a nice air conditioned room. That will solve the problem of the HDD and motherboard overheating. Just buy some nice fans, electric cooling units, or if you really are worried, water cool the sucker.
Second, yes oil makes a great cooling system, but NOT vegetable oil. They ought to have bought a non-biological version so that it won't spoil and grow things. Anaerobic microbes building up on a motherboard is not a good thing. Not to mention the oil will loose consistancy then, and develop pockets of non-oil byproducts of anaerobic respiration. Mineral oil would work much better, and is nearly as cheap. A gallon of the stuff ought only run $10 or so, compared to $5 for vegetable oil. 2x the price, but it would never have to be changed.
Thirdly, I wonder why they feel the need to use oil for cooling at all, if the attenna is the only thing exposed (as I suggested earlier), heat from the sun won't really effect performance to much, and if it does, build a shade. If it is water proofing you are worried about, that is a slightly different story, but you can easily encase it in transparent plastic (but be careful that it doesn't warp em radition passing through it, this has to be quality stuff.
The idea in general is cool, but not very practical.
They are using the wrong type of oil for their project! For starts the oil is organic and will spoil, making things messy. Veggie oil is, in the family of fluidic heat conductors, a poor performer.
What they can use and is readily available at any store that sells Amateur radio gear or wholesale electrical supplies is transformer oil..
It's actually designed to be used in what the RF techs call dummy loads to conduct the heat away from the resistor banks that absorb the RF energy when they test transmitters. The stuff's most commonly used to wick away heat from electrial transformers, both at substations and the transformers hanging on the poles that supply 240 Volt AC to your home.
One COULD try to build a oil-cooling system on a custom PC, but the heat removal would not be as good as glycol/alchohol/water cooled system.
First rule of holes; When in one, stop digging.
...as they did not immerse the one component that is most vulnerable to heat: The harddisk. Of course the HDD is also the one thing that cannot survive being immersed.
In addition I do not see any external cooling or pipes to take the heat away, which means that the only difference is that the componets die a more uniform heat-death. Even though oil is not the best thing for convection. Viscosity is too high.
As "cool" as it looks, some intelligence and knowledge of physics and electronics is still non-optional for successful computer cooling.
One thing that could save the design is two long pipes, a pump and a heat-dump in the basement. And some cooling for the HDD.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted and ignored otherwise.
There's no reason to run more than half a meter of cable...
Use a small external radio, the sort that has three connectors: power, ethernet, antenna.
Keep the computer, hub, etc indoors and just run cat5 ethernet and some low voltage power cable up the the roof.
On the roof, mount the antenna and the radio. Put the radio in a small weatherpoof box, or even a reinforced plastic bag. You shouldn't need more than 40cm of cable. Heck, use a small adapter and mount the radio TO the antenna itself without any cable. Nearly zero loss.
These little radios aren't too expensive and can handle extreme temperatures. There's no reason to have long cable runs or a PCI/PCMCIA radio card.
People who typically do total immersion cooling use mineral oil. It is a non-organic oil, so it doesn't spoil. Doesn't conduct electricity either.
Mineral oil is very similar to transformer oil, which is what electricity companies use to keep the transformers cool.
The oil pressure will work on 'both sides' of the contacts, effectively cancelling itself, so that the oil won't be forced under the contacts. As a matter of fact, putting PCBs into (hydraulic) oil has been done in sub sea robotics applications and tested down to below 3000 meters. You'll have to change/modify some components (chrystals, capacitors), but most components handle both oil and pressure quite well over time, including non-soldered connectors. Moving parts, like fans and hard disks are a bad idea in oil, but in under water applications, cooling is rarely a problem.
I'd prefer mineral to olive oil, though...
Look! No sig!
They removed almost every part of water in the oil to avoid problems (yes, a bit can be dissolved into oil)
They could have used mineral oil wich is less acid and would have worked well.
The thing about HDs is like this: they *were* vacuum closed in the beginning, but in some really dry and heat condition (texas, etc) they kinda explosed. So they started putting some small valves on them to avoid this: so the oil goes in.
My english is sow-sow. Sowhat?
There's a very good reason to put the WiFi equipment on the roof as close to the antenna as possible. Wiring to connect the radio to the antenna incurs massive signal loss, or is very expensive (and still incurs loss). It's generally accepted in the 802.11 community networking community ;-) that the best place to put the AP is in a tupperware or other similar weather resistant container right next to the antenna.
Your suggestion about mineral oil is smart IMHO.
simon
home page
A few years ago at a boat show I saw a product at one of the booths which looked like a translucent brown liquid, intended as an electronics waterproofing sealant. It was such a long time ago I don't remember the name of the product, but as a demonstration they had a portable B&W television submerged in the stuff and it was still operating fine.
One of my friends used to work at KFC and he had told me how nasty the old oil would get while it sat outside awaiting pickup for disposal. I guess the little leftover bits of chicken probably had something to do with it, but I'm assuming vegatable oil is a pretty friendly enviorment for bacteria to thrive in nonetheless.
---
DRM is like antifreeze, to the MPAA/RIAA it's sweet, to the consumers it's poison.
FYI, for those that are wondering where to get this wonderfluid at..
i d= MFJ-21
Try here
http://www.mfjenterprises.com/products.php?prod
They sell it by the gallon and its pricey, but its the real mccoy.
First rule of holes; When in one, stop digging.
Comment removed based on user account deletion
Tension is actually a reference to voltage in this case.
This is not the first time it's done. Let me tell you the whole history...
Since three years ago, Iberian hackers hold an annual meeting, called HackMeeting.
The first one (code named hmbcn00) took place in Barcelona (Catalonia), in a squat called Les Naus, in October 2000.
The second one (code named hmleioa01) took place in Leioa (Basque Country) also in a squatted house, the Udondo Gaztetxe, in September 2001.
Finally, last October, it was hold in Madrid the 3rd HackMeeting (code named madhack02).
As the previous meetings, it took place in a squat (El Laboratorio). This time gathered about 600 hackers.
It's not determined yet where the next HackMeeting will take place. Maybe somewhere in the countryside in Aragón.
Well, let's come back to the oil-powered PC.
In every hackmeeting there is a computer room, separated from the talks room. In the 3rd HackMeeting, the local HackLab (called Wau Holland 2001) had assembled a PC, put it in oil and placed in the computer room for public use.
I've placed a selection of pictures of the computer in oil (shot by Maky and Fernando Vicente) in my personal home page. Hope you like them.
Greetings,
Quique
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Knowing something about wireless and microwaves should tell you that we use to put the computers on the roof cos' in that signal we send, in 2'4 Ghz, we can loose it all in only 2 or 3 meters of wiring. So, we put it up.
;D
Here on spain our limit on signal power is 100mW. Lower than in USA as i know. And PigTails are cheaper in USA
See ya