11 ms·
The fanless heatsink: Silent, dust-immune, and almost ready for prime time
- simonbarker87 14y agoSimple idea, seems obvious when you think about it. Glad this wasn't just a Peltier device
- ojbyrne 14y ago"fanless" seems like unnecessary hyperbole. The heatsink is a fan, which is cool enough that it doesn't need to be oversold.
- m_eiman 14y agoIt's also not "silent", but rather "quiet". Marketing overload.
- deleted 14y ago[deleted]
- sliverstorm 14y agoImpellers probably aren't technically fans, but I agree with you.
- InclinedPlane 14y agohttp://en.wikipedia.org/wiki/Centrifugal_fan http://en.wikipedia.org/wiki/Centrifugal_fan
- bobbles 14y agoAlso, anyone that never turns off their computer would know that 'stopping' isn't required for dust to build up on the fan blades, dust will quite easily build up on even moving parts.
- johnpmayer 14y agoI'm somewhat confused; do demonstrate how quiet it is, they turn off the loud motor that keeps it running?
- latch 14y agoBecause it's a prototype without noise filters or any other attempt to reduce motor noise. His point in turning off the motor was to show that there's little noise caused by the blades chopping through the air - which is where fan noise actually comes from.
- moe 14y agoYou are probably right. Still, why didn't they just attach a normal fan-motor and then compare that side-by-side to a standard-fan? It always seems a little fishy when a marketing-video does anything but the obvious.
- latch 14y agoIf I had to guess I'd say it's because the video is targeted at people for which this will be obvious. They aren't looking to sell this directly to consumers. They want to license the cooling technology. As far as they are concerned, the noise of the motor is probably as irrelevant as the bracket's color.
- miahi 14y agoI think what you actually hear is coil noise from the fast switching of the current in motor's coils. The motor they use looks and sounds more like a HDD motor more than a normal fan motor - optimized for constant speed under quite a heavy load. The fan motors work in a similar way, but they use less power and less coils in a bigger enclosed space, so they can be better optimized for sound.
- robertfw 14y agoIn a production version the noise is largely caused by the air flow, whereas the motor noise would be cut down/eliminated by casing which is not present in the development version
- excuse-me 14y agoI wonder how cheap and reliable are the bearings needed to run a 2000rpm 'fan' 1/1000" above a heat pipe, while being vibrated by hard drives and PSU fans, shaken around in laptops. Generally you can have bearings that are small/fast/precise or cheap - generally not all 4.
- nickolai 14y agoI was under the impression that this used a similar principle to the one that keeps hard drive heads in place. So some reasonable amount of vibration should not be an issue. On the other hand, assuming a reliability similiar to hard drives, failures will happen. and in worst case, will send a weighty heatsink spinning at 2krpm flying inside your computer case. Given how collision-unfriendly that baby looks, its not something i would want to happen inside my desktop box.
- excuse-me 14y agoHard drive bearings are big and expensive! But the heads are mostly kept above the surface by aerodynamic effects - effectively they are held in a thin air film which stops them touching the platter.
- hollerith 14y agoThis new heat sink / fan is like the heads in the hard drive: it floats on a thin film of air. Consequently, it does not need any conventional bearings. The video describes it as "using an air bearing".
- excuse-me 14y agoIt isn't an air-bearing by any normal use of the term. It still needs a radial bearing to attach it to the motor - especially if you aren't mounting this perfectly flat and level. It can use an air cushion effect to reduce the planarity demands of the bearing to keep the heat transfer surfaces parallel - but this is very different to 'floating' a 10mg sprung drive head
- deleted 14y ago[deleted]
- moonboots 14y agoDoes this heatsink work when it's mounted vertically? The "hydroplaning"/floating effect seems to suggest the heatsink must be resting on the base instead of suspended sideways.
- deleted 14y ago[deleted]
- deleted 14y ago[deleted]
- thrownawayfan 14y agoFrom the slides at https://ip.sandia.gov/techpdfs/Sandia%20Cooler%20presentation.pdf https://ip.sandia.gov/techpdfs/Sandia%20Cooler%20presentatio... >Q: Can the device be mounted in any orientation? >A: Yes—the air bearing assembly is held together by magnetic attraction (between the stator and permanent-magnet rotor).
- stevewilber 14y agoThe video mentions that transferring heat to the impeller is a challenge, but it wasn't clear to me how they overcame this. Is the space between the CPU and the impeller so small that heat can be transferred efficiently? If that is the case, I wonder how cheaply these could be produced given the incredibly tight clearance.
- thrownawayfan 14y agoThere's a whitepaper available here http://prod.sandia.gov/techlib/access-control.cgi/2010/100258.pdf http://prod.sandia.gov/techlib/access-control.cgi/2010/10025... Their data suggests that the air gap provides minimal resistance to the flow of heat. As for the clearance, they've stated that unusually high-precision manufacturing is not required for the two surfaces.
- nialo 14y agoRe: clearance, while .001" clearance isn't something I'd want in a design particularly, modern machine tools are good enough that you get flatness and surface finish good enough to not have problems at .001" clearance basically free on any machined surface.
- excuse-me 14y agoYes it's a radiative/convective coupling in the thin air gap. Although the thermal conductivity of an air gap is normally low - which is why you have double glazed windows - it gets complicated if the gap is much less than the free path in the air
- Uchikoma 14y agoThe fanless heatsink is a fan. Duh. YMMV but I'd not call it fanless.
- freehunter 14y ago"Fanless" might be a bit of a stretch, but it doesn't need another fan.
- Uchikoma 14y agoA bit of a stretch, but I'd not call a car "engineless" just because it does not need another engine ;-)
- freehunter 14y agoIf every car before it needed both an engine and a car, and now there's a car that is its own engine, I would give them some leeway to call it an engineless car. The big draw here is that the heat sink is the same as the fan, instead of needing to buy both a heatsink and a heatsink fan. "Fanless" is still weird, I'd prefer to call it integrated.
- deleted 14y ago[deleted]
- hetman 14y agoI remember seeing this a year ago. It's a bit worrying that in that time they still haven't gotten around to building a prototype that will be as quiet as the claimed final product. While that doesn't mean it can't be done, it may point to deeper issues in the project such as yet unaddressed technical challenges or lack of funding (which might in turn suggest lack of investor conviction). Personally I'm curious what the failure rate will look like with these things. Given it will probably be higher than existing PC cooling fans which are moving lighter loads, this may indeed be a problem.
- adventureful 14y agoMost larger manufacturing companies move at a glacier pace. I could see Apple making a quick decision to use these and then having them in models within a year, but few other manufacturing companies are willing to move like that.
- K2h 14y agoMy impression was that Apple intentionally lagged the cutting edge curve to error on stability and sound user experience. I would be very surprised to see them go in the direction of moving parts - instead I would expect them to continue in the direction of all solid state (no moving parts) as much as possible.
- vitalique 14y agoI think what you've seen is this[1] article at extremetech.com or may be the HN post[2] inspired by that article. Both are quite interesting to read (article provided some original research in PDF, HN discussion provided some comments from the fan engineers). Besides your question about failure rate, I'm also wondering if such a massive thing going at 2000 rpm becomes a dangerous neighbor to other stuff on the motherboard (especially in the case of failure) and to the motherboard itself. I figure the vibration this kind of fan generates may be rather noticeable. [1] http://www.extremetech.com/extreme/89710-the-fanless-spinning-heatsink-the-heatsink-is-the-fan http://www.extremetech.com/extreme/89710-the-fanless-spinnin... [2] http://news.ycombinator.com/item?id=2754725 http://news.ycombinator.com/item?id=2754725
- deleted 14y ago[deleted]
- tadfisher 14y agoI'm not sure what problem this is trying to solve. I have a truly fanless heatsink [1] that is ducted to a 120mm case fan at 1000RPM, which is guaranteed to produce less noise than a 2000RPM rotating metal disaster. A plus is that there is no air gap necessitating such a high rotation speed. [1] http://www.thermalright.com/new_a_page/product_page/cpu/hr01plus/product_cpu_cooler_hr01plus.htm http://www.thermalright.com/new_a_page/product_page/cpu/hr01...
- riobard 14y agoYou won't be able to fit that fanless heatsink inside a laptop. It's just way too big.
- tadfisher 14y agoIndeed. I hadn't thought of that.
- thrownawayfan 14y agoOf course, fitting this into a laptop would be problematic as well.
- Retric 14y agoYou could probably use a heat pipe to the back of a laptop's screen. The problem becomes the joint where the screen connects to the case, but a flexible pipe is not out of the question... To the patent office ;0
- colinshark 14y agoThe demo unit is presumably rated for about 150 watts. A unit rated for the ~40 watts that a laptop creates would be smaller and shorter.
- nessus42 14y agoThe title of the article clearly states some of the problems this is trying to solve. E.g., "dust-immune". Also, they claim the heat sink to be relatively quiet (under 30dBa).
- Too 14y agoLast time this was one hacker news someone suggested mounting the chip onto the heatsink and spin the whole thing, without any thermally conductive bearing. Still an awesome idea imo.
- kintamanimatt 14y agoHow do you connect the chip to the motherboard though?
- jholman 14y agoI missed the article last time, but I had this thought too, on reading it this time around. The challenge, obviously, is moving data on and off of the spinning element. I assume one would stack the CPU, the GPU, the mobo, the RAM, etc, up along the axis of rotation. It's certainly easy enough to get keyboard and mouse and audio get on and off the spindle via wireless... but what are the costs (in money and in latency) to get higher-bandwidth signals on and off, like video, and like main storage?
- tedunangst 14y agoif every conventional heatsink in the US was replaced with a Sandia Cooler, the country would use 7% less electricity. For the most part, these savings would come from air conditioning and refrigeration systems How does that work? Is the same amount of heat not being expelled from the chip into the room? Does transferring the heat with a smaller fan somehow make it smaller heat?
- deleted 14y ago[deleted]
- capnrefsmmat 14y agoTransferring heat with a smaller fan requires less power to run the fan. For a given amount of electricity, the Sandia Cooler can extract more heat from the processor, so it requires less electricity to keep the processor cool.
- tedunangst 14y ago7% of the electricity in a data center goes to spinning CPU fans? I do not believe that.
- rosser 14y agoNot just CPU fans. FTFA, and the latter part of which was included in the GP's quote: "an ideal replacement for just about every fan-and-heatsink installation in the world... For the most part, these savings would come from air conditioning and refrigeration systems..."
- tedunangst 14y agoI know, I read that. The impression I got from the article was that these new heatsinks were going to be used on the CPUs and that somehow that would generate less heat. e.g, if Intel makes a lower power chip, a lot of savings will come from AC, even though Intel isn't making AC systems. It was not obvious to me (and I still have my doubts) that "every fan-and-heatsink" was referring to AC systems as well as CPU heatsinks.
- gouranga 14y agoI was hoping to see something like a peltier heat pump which has no mechanical parts.
- miahi 14y agoA Peltier element only moves the heat from one side to the other. If you don't have some device to cool the hot side, the element will overheat and burn - so you still need a big heat exchanger to dissipate the heat into the air. Also, Peltiers are not really energy efficient.
- gouranga 14y agoI said 'like' - I'm aware of the problems :(
- blt 14y agoThat part looks really expensive to manufacture. It's machined. Can they make it out of molded plastic (like fans) or sheet metal (like CPU heatsinks)?
- miahi 14y agoMost of the original (boxed) CPU fans are machined. The sheet metal fans are 3rd party and they need costly heatpipes to move the heat away from the (machined) CPU base. It will be costly because the machined metal fan will need great balance and a good polish to stay quietly floating above the base and not jump and rip through the computer's case. You cannot use plastic as it has a lousy thermal conductivity. You cannot use copper because great thermal conductivity (2x better than Al) comes with greater weight (3 times the density of Al).
- jmsduran 14y agoThis is a very interesting heatsink design. That said, having a finned heatsink spinning at 2000+ RPM seems potentially dangerous, especially if someone were to touch it with their bare fingers while it's operating.
- huhtenberg 14y agoGiven that it sucks the air in through the central part, it must be spinning counter clockwise, with external fin ends pointing away from the direction of spinning. Not 100% safe, but not a finger chopper either.
- verroq 14y agoIt'd suck to have it grind against any cables.
- jholman 14y agoMany of the questions in this comments thread (e.g. safety, e.g. vertical mounting, e.g. cost associated with the bearings, e.g. the basis of the 7% figure) are already answered directly or indirectly in a year-old Q&A article that was linked from TFA. http://www.extremetech.com/computing/90272-the-fanless-spinning-heatsink-your-questions-answered-by-the-inventor?print http://www.extremetech.com/computing/90272-the-fanless-spinn... Not very good-HN-citizen-ish to post questions without putting any work at all into looking for the answers, is it?
- robomartin 14y agoFrom the article: "This centrifugal force is what gives the Sandia Cooler such massive efficiency, too." That is not correct. The efficiency boost comes from the very efficient transfer of heat from the CPU to the spinning fan/heat exchanger by, effectively, using the very thin air-gap under the impeller. The rotation of the impeller breaks the boundary layer in the airgap and you get good heat transfer across a very thin gap. The airflow over the machined aluminum blades and, in general, the rotation of the entire impeller assembly, serve to keep the heat exchanger free from dust accumulation (which restricts heat flow). Of course, as many have pointed out, it remains to be seen how easily this concept translates to a mass-manufactured low-cost solution in terms of performance and reliability under varying conditions. I've done a ton of heat flow FEA work when working on various approaches to cool a custom high-power LED array (1,500W power-in). We could get reasonable results with complex forced-air solutions and relatively expensive custom machined heatsinks as well as carefully modeled airflow controls. In these cases the solutions were always very large (volume). When we switched to fluid-based cooling things changed dramatically. One of the design challenges was to maintain a narrow delta-T across the LED array. This is because thermal uniformity was required in order to have uniform performance across the array. The fluid solution, with some tricks, could easily achieve ten times better thermal uniformity than the air-cooled approach. And, in addition to this, cool the entire array to a much lower final temperature. A fluid cooling system was constructed using only a small fluid pump and no air-moving fans at all. A passive natural convection radiator could easily handle the heat-load in a normal air-conditioned office environment. While I have not looked at the specific case of cooling a CPU, based on my experience I have to say that far greater gains can be had by rapidly moving heat from the CPU surface using fluid-based cooling. This, effectively, creates the opportunity for much greater surface extension than can reasonably be applied to the small surface area of a CPU. Again, I have never studied CPU cooling, but I am not sure that this 150W cooling limit applies to fluid-based cooling. I can see building a systems that can very easily move 150W, or even double that, using a relatively simple fluidic cooler. At some level it is a matter of how many molecules of the fluid you can move across the CPU-side heat exchanger per unit time. The answer to that is "a lot". I can't see the Sandia or any other pure air-based cooling system used for CPU cooling at the extremes. The assembly would have to be very precisely manufactured and lots of work would have to be done in order to ensure that vibrations and harmonics of the motor drive system itself don't cause damage to the circuit board. If the system needs to have an impeller spinning at 2K RPM or more, lots of work needs to go into making it safe for servicing as a metal impeller like that can shred fingers in an instant. Finally, there's the question of the mass of the spinning impeller. In order to transfer heat into the impeller blades you are limited to certain geometry. If the spinning base and/or the blades get too thin you simply won't be able to move the heat out no matter how well it can move from the stationary plate up to the revolving disk. This is critical and it means that there are certain minimum geometry constraints that are likely to make the impeller somewhat massive. From my FEA work on heat transfer I know that you can only go so thin on blades before they become useless past a few millimeters above the heatsink base-plate. The same is the case here. What I can see is the use of this concept to create a fluid based solution that uses a liquid to quickly move heat from a CPU to a much larger heat exchanger that uses the Sandia heatsink to move heat into the surrounding air, and, thereby, cool the CPU. Even at that, I'd like to see data comparing conventional forced-air convection cooling of the external heat exchanger and even a comparison to a natural convection solution.
- dfrey 14y agoIf this ever makes it to mass market, there will be some bloody knuckles on people who are trying to make small adjustments to the inside of their computer case while it is running. It's basically 100 butter knives spinning at 2000 rpm.
- hexagonal 14y agoPrevious thread: https://news.ycombinator.com/item?id=2754725 https://news.ycombinator.com/item?id=2754725
- dazmax 14y agoI'm hoping Apple is waiting for this to be ready before they update the Mac Pro hardware.
- veemjeem 14y agounlikely. if you look inside a macpro, you'd see that they have 2 giant fans that cool the cpu & ram. They pipe the air so that it flows over the cpu heatsink & ram, but no other components. There's another fan for cooling the rest of the system. Apple would have to re-engineer the entire case if they wanted to use the impeller design.
- robwgibbons 14y agoFalse. I am a fan of this heatsink.
- mrgreenfur 14y agoThis is a year old. Why did slashdot move here?