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Science Technology

Sapphire: A Liquid That Won't Get Things Wet 843

eaglebtc writes "Tuesday on Good Morning America, a representative from Tyco Fire & Security demonstrated an amazing new substance called Sapphire: a water-like fluid that does not get things wet. He filled a small fish tank with Sapphire and submerged a book, a laptop, and a flat panel TV. Both electronics were turned on when submerged; all three items came out completely unharmed. Click here for a slideshow of the demonstration. The official name for Sapphire is actually Novec 1230. Read about it here (PDF). Tyco sees practical applications of Sapphire in fire extinguisher systems for museums and libraries. By the same token of practicality, regular readers of Slashdot probably have something else in mind: total-immersion watercooling. Just think of the possibilities!"
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Sapphire: A Liquid That Won't Get Things Wet

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  • Fluorocarbons (Score:5, Interesting)

    by BWJones ( 18351 ) * on Wednesday April 14, 2004 @01:45PM (#8861696) Homepage Journal
    Hmmmm. This sounds like the fluorocarbons that we used to bathe the insides of Cray supercomputers with. They were pretty cool with little windows that one could look in and see "waterfalls" of fluorocarbon flowing over the circuitboards and components to keep them cool.

    Of course we had to have an entire floor below us dedicated to refrigeration, but hey. Governments can afford this kind of stuff.

  • Pricey (Score:5, Interesting)

    by Brento ( 26177 ) * <brento.brentozar@com> on Wednesday April 14, 2004 @01:45PM (#8861698) Homepage
    If they're targeting it for fire prevention applications, not industrial cooling, then you can bet it's pretty pricey.

    After all, 3M's not stupid: they price things correctly. These are the guys behind the Post-It Note.
  • Re:Uhm (Score:5, Interesting)

    by strictnein ( 318940 ) * <{strictfoo-slashdot} {at} {yahoo.com}> on Wednesday April 14, 2004 @01:46PM (#8861709) Homepage Journal
    I'm no expert but if something's on fire, getting it wet is the least of your worries.

    Yep, you are no expert. In many fires by far the most damage is not caused by the fire itself, but by the massive amounts of water used to put it out.
  • Re:"Water"-cooling (Score:1, Interesting)

    by davebarz ( 546161 ) * <david.barzelay@net> on Wednesday April 14, 2004 @01:47PM (#8861749) Homepage
    how useful would it still be for cooling purposes if it were a gas?
    Potentially very useful depending on the properties of that gas.
  • by ShdwStkr ( 454413 ) on Wednesday April 14, 2004 @01:48PM (#8861761)
    how to you clean it up? Or pick it up? Say, after it's been used to put out a fire? Or does some 'special' cloth absorb it?

    -j
  • Re:"Water"-cooling (Score:5, Interesting)

    by stereoroid ( 234317 ) on Wednesday April 14, 2004 @01:48PM (#8861764) Homepage Journal

    The actual usefulness of the fluid in any state depends on the specific heat capacity, which I can't see 'coz the site is /.'d ...

    Since the phase change itself is be a major energy-absorber, that could be very helpful indeed as long as fresh condensed fluid comes in after a radiator of some sort.

  • Re:Distilled Water? (Score:2, Interesting)

    by Anonymous Coward on Wednesday April 14, 2004 @01:53PM (#8861849)
    Water ionizes itself. There is a certain amount of the reaction 2 H20 -> H30+ + OH-. While very distilled water does not conduct electricity very well, it is still a highly polar substance and will still foul things up.
  • Re:Distilled Water? (Score:3, Interesting)

    by tstoneman ( 589372 ) on Wednesday April 14, 2004 @01:53PM (#8861852)
    Water naturally ionized into H+ and OH-, which is the cause of the conduction of water.
  • Re:"Water"-cooling (Score:3, Interesting)

    by Chiasmus_ ( 171285 ) on Wednesday April 14, 2004 @01:53PM (#8861861) Journal
    this stuff has a boiling point of 49.2C (120.6F)

    I'm sure that's the boiling point at standard atmospheric pressure at sea level, although the page is slashdotted, so I can't verify that.

    It's not difficult to raise a liquid's boiling point by pressurizing it. Cooks do it all the time: it's called a pressure cooker.

    But really, there's no reason to bother with that. Cooling a processor isn't about dunking a computer in a liquid and letting the heat evenly distribute. You're gonna want to chill it, no? It's probably more relevant to talk about the liquid's freezing point than its boiling point.
  • Re:"Water"-cooling (Score:5, Interesting)

    by Phurd Phlegm ( 241627 ) on Wednesday April 14, 2004 @01:54PM (#8861875)
    yes... but no-one's concerned about reusing the water you used to put out the fire. coolant, on the other hand, should stick around for more than a few seconds before it bubbles off into the atmosphere.

    If you put it deep enough in the fluid, the bubbles will condense on the way up. If the heat of vaporization is anything reasonable, this should work quite well to remove heat from your chip--the fluid changing to a gas absorbs a bunch of heat, and then swims away with it, while more cool fluid rushes in to take its place. Probably look cool, too.

  • Fluorinert (Score:5, Interesting)

    by Skyshadow ( 508 ) on Wednesday April 14, 2004 @01:56PM (#8861900) Homepage
    I was in intern at the Chippewa Falls offices of Cray (well, SGI, but we all called it Cray) back in 1999.

    I seem to remember hearing that the fluorinert they cooled the processors with was perfectly safe unless turned into a gas, in which case it was roughly as toxic as mustard gas. So, if there was ever an electrical fault in one of the machines that caused the coolant to boil off, there was a distinct possibility that you'd end up with a few dead operators.

    Can anyone confirm/deny this? Actually, don't deny -- this is one of my best geek stories.

  • Re:Distilled Water? (Score:5, Interesting)

    by sacremon ( 244448 ) on Wednesday April 14, 2004 @01:56PM (#8861901)
    Sure, until ions are leeched out of the components, allowing a current to flow.

    In a lab that I worked in we had water that had been passed through several kinds of filters and ion exchangers. You were good to go when the machine said that it had 10+ megaohm of resistance. We stored the water in clean glass bottles, but after about a week had to dump it because the ions leeched from the glass.
  • Re:Safe? (Score:3, Interesting)

    by HeghmoH ( 13204 ) on Wednesday April 14, 2004 @01:57PM (#8861909) Homepage Journal
    That doesn't really relate. Caffeine is more toxic than plutonium, but I don't see anyone claiming that caffeine is environmentally unsafe.
  • Re:"Water"-cooling (Score:2, Interesting)

    by promethean_spark ( 696560 ) on Wednesday April 14, 2004 @01:57PM (#8861922)
    The bubbles would really help the convection current along too. The whole system could also be enclosed so none of the coolant evaporates. A pressure switch on the enclosure could turn the system off when it reached dangerous pressures or temperatures.
  • Pure H2O (Score:3, Interesting)

    by javatips ( 66293 ) on Wednesday April 14, 2004 @01:58PM (#8861926) Homepage
    It is my understanding that H2O (without any minerals) is not a conductive material. So could probably put my laptop (It would have to be clean to not introduce minerals) in pure H2O and it would not be affected.

    Am I right?
  • Re:Ted Kennedy (Score:1, Interesting)

    by bombadillo ( 706765 ) on Wednesday April 14, 2004 @01:58PM (#8861938)
    Same for the Bush's and Cheney. Cheney has 2 or 3 DUI's. W Bush was arrested for a DUI. Mrs. W Bush killed her best friend when she ran into her car. Yep, most of the "Pillars" of our community suck!
  • by suso ( 153703 ) on Wednesday April 14, 2004 @02:00PM (#8861957) Journal
    I know that being wet might not be the only thing that puts a fire out, after all, look at gasoline. But I'm curious to know why Tyco Fire & Security came out with this. How does it put out a fire?
    Would be great for machine rooms.
  • by Big Bob the Finder ( 714285 ) on Wednesday April 14, 2004 @02:07PM (#8862068) Homepage Journal
    I've often wondered if ultrapure water could be employed if the substrate were properly prepared. In other words, if the components had a very thin passivating or inerting layer that would prevent ions from leaching into solution, and then the water was very high purity (higher than distilled), you *could* immerse the components. Ultrapure water straight out of the tap has a resistance of 18.3 million ohms per centimeter (until it hits air, and carbon dioxide drops it to about 500,000 ohms).

    So, if you could exclude air, coat the components, and then recirculate the ultrapure water through a resin bed (which is how it's made ultrapure in the first place), it *could* be done- but it would be a lot of work. Plus, very pure water is surprisingly corrosive, so the inerting layer would have to be pretty specific, like the polyethylene that coats the inside of soda cans (cheap but effective).

    Water has the benefit of having a large specific heat (4.18 kJ/kg), which is about as good as it gets. While Novec 1230 is good stuff, it has low specific heat (1.103 kJ/kg). It's a trade-off, though, since you can't get pure water below 0 C without the risk of it freezing, unlike Novec, which gets down to -108 C.

  • Read the datasheet! (Score:4, Interesting)

    by rarose ( 36450 ) <rob.robamy@com> on Wednesday April 14, 2004 @02:09PM (#8862097)
    It puts out a fire by cooling the combusting materials. The data sheet takes pains to point out that this is different from halon systems that deprive the fire of oxygen.
  • by CrystalFalcon ( 233559 ) on Wednesday April 14, 2004 @02:10PM (#8862103) Homepage
    They might have some information there about how well the stuff will conduct heat, but I got a lousy grade in Chemistry, so I'll leave it to the experts. ;)

    A liquid conducts heat EXTREMELY well. You're thinking in terms of a solid, where atoms are fixed and have to transfer energy to each other. However, in a liquid, if one portion of the liquid is heated, this creates a stream of molecules in the liquid to disperse the heat. The heated molecules will actively move away from the heat source, giving room to cooler liquid molecules, which is a hell of a lot more efficient than normal solid-state heat conductivity.

    Additionally, it has an heat capacitivity of about 1.1 kJ/kg/degree C, which compares to 4.2 for water. This means that 1.1 kJ (1.1 kW for one second) will heat one kilogram of the stuff one degree Celsius.

    One can use this number for some interesting math. A normal box draws maybe 250W, all of which becomes heat. The density of the stuff is 160% of water's. I guesstimate that my tower will hold about twelve liters of water, or about 20 kg of this stuff.

    (Note the scientifically correct notation "this stuff".)

    Anyway, 20 kg exposed to 250W means that this stuff will heat by 0.75 degrees C every minute if the heat is not dissipated. Assuming a room temperature of 25 deg C, and an electronics-critical point of 45 deg C (the upper bound of operating temperature for some things I've seen; hell, some even have 40 tops), we have a span of 20 degrees, or about 30 minutes of operation until components are out of spec in their operating environment.

    Again, this assumes that no heat is dissipated. A miditower probably has about 0.5 to 0.75 square meters of dissipating surface, with good heat transfer from this stuff inside.

    Anybody knows if hard drives are built to operate immersed in liquid? :-)
  • convenient timing... (Score:2, Interesting)

    by Spatula Sam ( 770957 ) * on Wednesday April 14, 2004 @02:11PM (#8862136)
    The cynic in me has to wonder if this announcement/demonstration hasn't been conveniently timed to draw attention away from the fact that Tyco's former CEO is currently on trial for looting the company and a lot of its former board members are also facing criminal charges... "Hey! Look over there! Water that doesn't get stuff wet!" //ss
  • Re:"Water"-cooling (Score:5, Interesting)

    by psychofox ( 92356 ) on Wednesday April 14, 2004 @02:16PM (#8862180)
    You have to be careful with 3M's Fluorinert: Mustard gas doesn't sound too pleasant to me!

    Mustard gas [beowulf.org]

    Corporate site for Fluorinert [3m.com]

  • Total immersion (Score:2, Interesting)

    by SquadBoy ( 167263 ) on Wednesday April 14, 2004 @02:22PM (#8862256) Homepage Journal
    overclocking has been being done for years with mineral oil.
  • Re:"Water"-cooling (Score:5, Interesting)

    by kcdoodle ( 754976 ) on Wednesday April 14, 2004 @02:23PM (#8862272)
    A good cooling setup would have enough flow to keep the liquid from boiling.

    With a high enough recirculation flow rate, any boiling the would take place would be at the chip. Small bubbles would form and be swept away by the fluid flow.

    This process is called "Nucleate Boiling" and is the best heat transfer method there is. The latent heat of vaporization is absorbed by the liquid in it's phase change to a gas. Then the tiny gas bubbles are swept away by the fluid flow and the gas bubbles collapse, giving their latent heat to the surrounding fluid. This heat is later removed by the cooling radiator at the other end.

    As long as the bulk temperature of the fluid stays well below the boiling point and the fluid flow is sufficent to strip the small bubbles that form on the heat source surface, this is really the best setup imaginable!

    I live the greatest adventure anyone could want -- Tosk the Hunted.
  • Re:Pure H2O (Score:3, Interesting)

    by Control Group ( 105494 ) * on Wednesday April 14, 2004 @02:25PM (#8862284) Homepage
    Technically, yes, but pure water is a very strong solvent (strong enough to give you mild burns if you pour it on your skin); something in your laptop is guaranteed to dissolve into the water, thereby making the solution conductive.

    And then, of course, *zap*

  • Get off my planet (Score:3, Interesting)

    by MacFury ( 659201 ) <me.johnkramlich@com> on Wednesday April 14, 2004 @02:29PM (#8862329) Homepage
    what happens to the environment?

    What planet are you from? Here on earth we only care about what happens to their stock price!

    Get off my planet, you're not ruining it for the rest of us. :-)

  • Re:Fluorinert (Score:2, Interesting)

    by jonin ( 471268 ) on Wednesday April 14, 2004 @02:30PM (#8862335)
    The movie "The Abyss" gives a totally incorrect view about breathing liquids. People are not meant to breath liquids and don't unless they enjoy dying. As a fetus and until you are born your lungs are collapsed. It is not until birth and you take your first forceful breath does anything enter your lungs. One of the first things you have to do when a baby is born is suction out ithe nose and mouth because the amniotic fluid can cause infection in the lungs. The fetus receives oxygen through the blood stream from the placenta until birth.

    As far as Flourinert being used for deep diving, I think the poster is just completely incorrect. I have seen no valid evidence of liquid breathing. Most deep divers use Trimix (a mixture of oxygen, nitrogen, and helium.) One of the major challenges of breathing liquids, other than your alveoli require a gas exchange not likely to happen with a liquid, is how do you circulate the liquid from inside the lungs to the outside environment. Your diaphram and accessory muscles don't have enough strenght to move mass quantities of liquid.
  • not an ozone killer (Score:2, Interesting)

    by nallen ( 458389 ) on Wednesday April 14, 2004 @02:34PM (#8862378) Homepage
    It was developed as a ozone same halon replacement, so no worries there.

    As further explanation, the presence of fluorine atoms alone doesn't make a ozone depleting compound. CFCs are a problem due to the chlorines getting into the upper atomosphere, the clorine radical is a catalyst for the decomposition of O3. The fluorines aren't an issue since F radicals are too reactive to exist for a long period of time.

    Also, the 3M compound is too heavy to make it up to the ozone layer, CFCs were a combination of inertness to the troposphereic environment and being light enough to rise to the ozone layer.

  • Re:"Water"-cooling (Score:2, Interesting)

    by nameer ( 706715 ) on Wednesday April 14, 2004 @02:36PM (#8862402)
    Been there, done that. Here is a snippet from a quick search on the Cray II [tmeg.com]. I'm sure someone else will find a better link, but:

    The CRAY 2 was completely flouronics cooled. The cooling fluid, made by 3M, allowed the whole computer to be immersed in the electrically insulated fluid, and yet conduct the heat away by conduction and ebullient vaporization. It looked much like a fish tank.

  • Re:"Water"-cooling (Score:3, Interesting)

    by rattler14 ( 459782 ) on Wednesday April 14, 2004 @02:38PM (#8862440)
    Offtopic, but the submitter opened the door: according to their specs sheet (PDF warning), this stuff has a boiling point of 49.2C (120.6F). Processors burn hotter than that, how useful would it still be for cooling purposes if it were a gas?

    But remember, this is at ONE atmosphere or "standard" pressure. It is quite possible that in a relatively small pressure vessel with leads etched through it, that the boiling point could be raised. How much, that is something that has to figured out, but it's not completely unreasonable.

    Also, processors burn hotter than 120F because the cooling sucks. If a liquid were to be well circulated, it might be possible to keep the temperature of the outside of the heat sink at a reasonable temp (~100F). But that will depend mainly on the thermal diffusivity of the liquid as well as the circulation rate of the liquid.

    So yeah, a boiling point of 120F is pretty shitty, but there are reasonable ways around it, if the properties of this liquid have cooling properties that are worth the effort.
  • Re:"Water"-cooling (Score:5, Interesting)

    by ryepup ( 522994 ) on Wednesday April 14, 2004 @02:41PM (#8862473) Homepage
    on a more practical note, do you want a hermetically sealed case? Thats seems like it would be a lot more expensive and much more difficult to maintain. When you're hard drive dies, not only do you have to get a replacement drive and pop it in, you have to pop the seal on your case, drain some fluid, switch the hardware, then re-fill and re-seal the case.
  • by kendoka ( 473386 ) on Wednesday April 14, 2004 @02:43PM (#8862497)
    They've had a chemical called flourinert out for years - When I first came to my current place of work, you could see it coming out of the Cray we had in a little waterfall. It was kind of neat... As I understood it, oxygenated flourinert was what they dunked the little mouse into in the Abyss movie...
  • Re:Specs Data (Score:1, Interesting)

    by pragma_x ( 644215 ) on Wednesday April 14, 2004 @02:43PM (#8862507) Journal
    I thought the same thing... looks like a CFC to me.

    Actually, 3M's FAQ (the PDF linked in the post) claims that it has "zero ozone depletion potential". But it also seems to indicate that it degrades when it gets into contact with UV radiation (ie. keep it out of direct sunlinght). This leaves open the question: is it only ozone-safe as long as it doesn't decompose?

    Still the fluorine content of the chemical raises concerns beyond ozone depletion. This stuff may very well be even nastier to produce than, say, teflon. (With similar ecological and safety concerns)

    Additional info:
    http://www.tldp.com/issue/202/Notes_Fluorin e.htm
    http://www.fluoridealert.org/fluorosis-indi a.htm
  • Re:Fluorinert (Score:3, Interesting)

    by JayBlalock ( 635935 ) on Wednesday April 14, 2004 @02:44PM (#8862518)
    Well, according to all the making-of stuff on the Abyss DVD, they really submerged a rat in the stuff and filmed it breathing. So unless they were flat-out lying, it's real.

    And besides that, if you watch the scene in question, there's just no way they could've built such a lifelike robo-rat. At least, not cheaply enough to make it worth the cost, compared to just faking the effect.

  • by pertinax18 ( 569045 ) on Wednesday April 14, 2004 @02:46PM (#8862537) Homepage
    There was a substance that had similar properties produced in the past, but that fire suppression liquid was damaging the ozone layer. The new substance by Tyco is supposed to be environmentally safe.
    I am no an expert in these matters but the checmical formula they give is: CF3CF2C(O)CF(CF3)2, which looks like any other CFC except for one key thing, no chlorine. It is the chlorine that breaks off normal CFCs like Freon (CCl2F2) when exposed to UV rays and in turn breaks down Ozone. However, Florine is also a very toxic chemical as it is in the same period as Chlorine and can also have the same reactions with Ozone. I am curious to see if this new compound actually is safe for the Ozone layer or is there simply some hand waving going on.
  • by Aumaden ( 598628 ) <Devon.C.Miller@nOsPaM.gmail.com> on Wednesday April 14, 2004 @02:48PM (#8862555) Journal
    Since the book came out dry, it would appear that paper cannot absorb Saphire. Given that, how do you clean it up? It's not always convenient, or even possible, to turn the heat up to 120.6F.
  • by gardyloo ( 512791 ) on Wednesday April 14, 2004 @02:57PM (#8862644)
    The way you clean up spilled Mercury is to sprinkle zinc dust all over, and then sweep it up. It's one of the very few toxic substances that Environmental Health and Safety people will let an "untrained" chemistry or physics person clean up without a lot of shoulder-peeking. Hell, they even hand out these "special" sponges, which are essentially just a regular sponge with zinc bits glued on.

    The point is that Mercury WILL stick to zinc (amalgam, anyone?) and copper, but zinc is a bit less toxic than copper to have around.

    Similarly, I work with 3M's fluorinert liquids quite a bit, although not for cooling. They're useful for some of their other properties (which I'm not revealing right now, because my research could get scooped -- that's science in action!), but the BEST property is that they're STABLE, and they're awfully nonreactive with organics (humans). There've been studies where fish were immersed in fluorinert liquids for long times. Just bubble some oxygen through the stuff so the fish can breathe, and choose the right density, and the fish do fine. Choose the wrong densities, though, and the fish'll be bobbing about on the surface, wondering how the hell to deflate their swim bladders.
  • by gardyloo ( 512791 ) on Wednesday April 14, 2004 @02:59PM (#8862666)
    Damn! And so the point is, to clean up fluorinert liquids, you pump the bulk of it into a holding tank to be reused (it's expensive stuff!), and put fans on the rest of it. Smells a little fruity for a while (it's not TOTALLY unreactive), but it's safe and almost sane to just vent the vapor to the outer air. There's no bloody way you'll get away with doing this with Hg.
  • Re:"Water"-cooling (Score:5, Interesting)

    by syn3rg ( 530741 ) on Wednesday April 14, 2004 @03:10PM (#8862785) Homepage
    Actually you're right. Hard drives aren't hermetically sealed either -- They have small holse to allow the air inside to expand or contract based on heat load. The liquid would get in. It might not fry your electronics, but I'll bet it'd give the heads a hard time. possibly even corrupt the disks.
  • Re:"Water"-cooling (Score:4, Interesting)

    by JWSmythe ( 446288 ) <jwsmytheNO@SPAMjwsmythe.com> on Wednesday April 14, 2004 @03:23PM (#8862900) Homepage Journal
    I think you have a definate point there. Moving parts would have more friction moving through (or in contact with) the denser matter. The motor in the hard drive would have to work harder, and the arms that the heads are attached to would be slower to move through the liquid than air. It makes me wonder why they haven't developed hard drives to work in a vacuum. With less friction due to the lack of air, the heads should move quite a bit faster.

    I suspect a dunking wouldn't allow any or enough water inside the hard drive, but continued use in such an environment would obviously allow the liquid in.

    And obviously it would make CDRoms very hard to use. :)

    But, it does sound like a good idea for a full submersion motherboard. But, you'd probably have to mount the motherboard so all the connectors (keyboard, mouse, etc) were on top, or it would leak.

    I'd be just a bit nervous of about having a power supply submerged.

    And what happens if there's any condensation, or the liquid gets contaminated by any sort of conductive material? The liquid may be non-conductive, but contaminants would be.

    It does sound like a better solution for current design liquid cooling systems. If they leak, it won't fry anything. That is assuming it conducts heat, rather than insulate from it.

  • Total sub (Score:4, Interesting)

    by JDizzy ( 85499 ) on Wednesday April 14, 2004 @03:23PM (#8862904) Homepage Journal
    Why would I use saphire, which is probably very expensive to appropriate, when I could just use mineral oil to do the same exact thing more cheaply? For those that are not aware, mineral oil doesn't conduct electricity either, although it *does* get things "wet". To be fair so does saphire, but the way it touches a surface is different, not unlike the way teflon touches things in an inert way. From what I hear saphire was invented for clean-room fire situations like at a data-center full of computers. This stuff will add an extra notch in the 99.9% uptime of any facility who has it.
  • by bl8n8r ( 649187 ) on Wednesday April 14, 2004 @03:31PM (#8862984)
    Until people started dieing off from being exposed to it. I think R-22 refrigerant has the same wonderful properties.
  • by pclminion ( 145572 ) on Wednesday April 14, 2004 @03:31PM (#8862986)
    Just to add to your list... I've tried it with ethylene glycol (antifreeze) and that doesn't work either :-)
  • Re:Mod Parent Up (Score:3, Interesting)

    by M1FCJ ( 586251 ) on Wednesday April 14, 2004 @03:35PM (#8863031) Homepage
    Now if I can remember my heat transfer lectures, boiling is pretty good at moving energy. What you don't want to do is having the bubbles stick to the surface. Usually you get rid of this problem with a gentle forced convection. The fluid pump should generate enough flow. In most cases a gas bubble generated by boiling is no worse than a typical solid-gas interface heat transfer. Convection will improve the matters in all cases.

    Also I believe the gpp is comparing apples with oranges. When you boil your kettle, these bubbles occur all the time but still the temperature of the heating element stays same until amount of cavity increases incredibly and the element heats up, the circuit gets open again. Kettles only have natural convection which is not enough to sustain the steady heat transfer between the fluid and the heating element.

  • Re:Fluorinert (Score:2, Interesting)

    by symbolic ( 11752 ) on Wednesday April 14, 2004 @03:36PM (#8863041)
    Burn enough refrigerant, or just teflon in an open flame, and you will die.

    I saw a news report about this, and it doesn't even require an open flame or "ruining" a pan - according to the reporter, all it requires is the same level of heat you'd use to fry bacon.
  • Re:"Water"-cooling (Score:4, Interesting)

    by Lord Kano ( 13027 ) on Wednesday April 14, 2004 @03:58PM (#8863226) Homepage Journal
    That's because if the fire is hot enough, it will "crack" the water molecules, liberating both oxygen and hydrogen -- which will of course make the fire much worse.

    There have been accidents in steel mills where someone allowed water to becomed trapped unter liquid steel, the problem is two fold first is like putting water on a grease fire the instant evaporation causes the hot grease (or steel) above it to explode and 4000 degree steel can cause the water to crack into H2 and O2. Very bad stuff.

    LK
  • Re:"Water"-cooling (Score:5, Interesting)

    by zulux ( 112259 ) on Wednesday April 14, 2004 @05:42PM (#8863613) Homepage Journal
    It makes me wonder why they haven't developed hard drives to work in a vacuum.

    Because gas makes it soo easy!

    As the hard-drive spins, it pulls in some air along with it at the surface. The read/write head literally floats above this fast moving airstream. This allows the head to be made cheeply - they don't have to have inteligent or actuators to keep the head right above the disk itself. They just float.

    If you read the spec sheets for most hard drives - they ususall have a limit of 10,000 ft. Above that, the air is not dense enough.

    One could argue, why don't the just presurise the drives and seal them off: I've heard that the drives need to out gas for a few months after manufacture.

  • Re:"Water"-cooling (Score:5, Interesting)

    by Beryllium Sphere(tm) ( 193358 ) on Wednesday April 14, 2004 @06:02PM (#8863826) Journal
    >Fire suppression systems such as those that use Halon (which was outlawed in the '90s due to its ozone-destroying side-effects) put out fires by displacing oxygen with some other gas.

    Halon's not a good example of the point you're making.

    Halon works at low concentrations, without displacing oxygen, by chemically jamming the chain of reactions in the combustion process. You could think of it as the opposite of a catalyst. The bromine atoms do it, by binding to free radicals that normally keep the fire going. Sorry, I've never found a good online description of exactly how this works.

    WAY back when, the manufacturer ran a TV commercial showing a guy in a chair surrounded by a ring of fire. They put out the fire with Halon to show that it didn't interfere with the guy's breathing.

    If it were just a matter of displacing oxygen, don't you think they would have used something cheaper?
  • Re:"Water"-cooling (Score:3, Interesting)

    by iamhassi ( 659463 ) on Wednesday April 14, 2004 @08:46PM (#8865380) Journal
    "Hard drives aren't hermetically sealed either -- They have small holse to allow the air inside to expand or contract based on heat load. The liquid would get in. It might not fry your electronics, but I'll bet it'd give the heads a hard time. possibly even corrupt the disks."

    While that makes sense, didn't you read the post?
    He filled a small fish tank with Sapphire and submerged a book, a laptop, and a flat panel TV. Both electronics were turned on when submerged; all three items came out completely unharmed.

    He submerged a laptop, which obviously has ventilation holes which likely lead to the hard drive. Laptop was completely unharmed, or so they say: just because it was working for the 5 seconds it was on TV doesn't mean it'll continue to function.

  • Tried it, ... (Score:2, Interesting)

    by Derf the ( 610150 ) on Thursday April 15, 2004 @05:00AM (#8867178)
    We draw very clean water from a spring, gravity feed it through polythene pipe straight to the house. One day I gravity feed this water straight into my office to a depth of 200mm [8 inches].

    An old P200 tower under the desk was running happily; immersed up to the bottom of the RAM chips! It never missed a beat.

    The UPS beside it [there to power the important things] fried beyond repair. The battery ionised stuff maybe, cause it corroded dramatically over the next few days.

    The P200 still ticks away in the corner.

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