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PC Fan of the Future?
baptiste writes "While we marvel at the latest CPU release or new motherboard chipset, we still put the same old fans in the neon lit cases and then complain that it is too loud. Well, maybe someone has finally come up with the next generation PC fan. Y.S. Tech has announced a new fan which is driven at the blade tips by a magnetic motor in the housing. Without the motor in the middle they claim a 30% airflow improvement meaning, potenitally, you could get the same airflow of today's fans at a lower RPM meaning less noise. They also claim the fan tips result in the bulk of fan noise. In this design they are sort of enclosed, reducing noise further. There is also a PDF datasheet available."
Check out their FAQ page for details about how to get a free sample fan for testing and reviewing. The only catch is that you must have a website, and presumably you are meant to post a review on your site.
Well, there's already a magnet sitting in the fan on your cpu right now...
Are these the ones you were thinking about?
http://www.zalman.co.kr/english/intro.htm
/ScumBag
"...the torque of motor becomes even much more powerful than ever."
They advertise the torque as being much higher than other fans, but of course it is. They've sacrificed RPM, therefore airflow:
"...you should not only look at the airflow and static pressure to determine whether T.M.D. FAN is better or worse than traditional motor fan."
And a lot of the reasoning behind the idea of a heatsink, is that you don't need to have all of the air flow at one point. It's spread out.
this fan has already had some discussion on the various case/cooling forums:
amdmb
ars
This is entirely correct: ask anyone from an aeronautics background: tip speed is king when you consider noise, and that's it. Huge effort goes into reducing the noise produced by the high blade tip speeds of turbo-prop engines.
If you want a quieter fan: slow the blade tip speed, simple as that. (although I think this new fan design does have advantages, particularly the increased air-flow near the fan axis).
Not quite. The caterpillar drive was a gigantic induction pump. Water moves in an electric field, similar to magnetism - generate a large enough field and you can get water moving at a decent pressure. Small induction pumps are fairly common in homebrew watercooling rigs on PCs.
For years the huge cooling fans like those on board train locomotives have used a neat trick to keep the noise down. Instead of placing the fan blades at equal angles from each other, they are offset by a small amount. This actually results in a lot MORE noise but it's all outside the human hearing range. The same trick works for small fans as well but no one ever seems to take advantage of it. You basically hear nothing but the motor. (By the way. Does anyone know if there is a manufacturer of these in existence? My computer could definitely use a fan upgrade.)
"Who is General Failure and why is he reading my disk?"
I emailed the manufacturers regarding the free tests. Here's what they said:
;) I wonder why?
Thank you very much for your high interests in Y.S. TECH's revolutionary new product: T.M.D. FAN (Tip-Magnetic Driving Fan).
After the announcement of the T.M.D. FAN, we have been receiving uncountable inquiries everyday to review the T.M.D. FAN, to obtain the T.M.D. FAN samples and to attain developing schedule. To deal with all of your inquiries and be fair to everyone, here is what Y.S. TECH would like you to follow. We appreciate for your cooperation in advance!
1. Please visit Y.S. TECH web site at http://www.ystech.com.tw to obtain the detailed information (including technical issues).
2. We hereby enclose some images (.jpg at 72 dpi) that you are very welcome to apply them to your web site's product review and news announcement.
3. After your post or announcement of the T.M.D. FAN in your web site, please inform us the links. Then we will deliver physical T.M.D. FAN samples (possibly with heatsink) for your test and review purpose. The samples will be delivered to you in the middle of April.
4. After your test on the T.M.D. FAN, you will be much appreciated, if you post the test results and comments in your web site. It doesn't matter the results or the comments are positive or negative. The general public needs the truth.
Here is the rough schedule for the dimensional development of the T.M.D.
FAN:
Now: 70x70x15mm is now available. It is targeted for Pentium 4 CPU cooler.
April: 70x70x15mm T.M.D. FAN will be shipped out to variable locations over the world.
May to June: 60x60x25mm, 80x80x25mm T.M. FAN will be released to the market. These two dimensions are targeted for AMD CPU cooler and case cooling.
Again, thank you very much for your interests in T.M.D. FAN!
Should you have any questions or comments, please feel free to contact us. Y.S. TECH will reply to you as soon as possible.
Note the "uncountable enquiries..
I think their attitude about the reviews is very good. It's a shame more companies aren't like that.
--
Andy
I've replaced my PS fan with a silencer fan from PC Power and cooling. Take out the old fan and replace with new one. String power wire out of the PS with the other wires, and connect to power connector. It's very quiet (rated at 20 dba), and has the same airflow as a regular PS fan.
> Did you know the Apple 2 had NO FAN at all?
Neither does the Tandy 1000 RL I've got sitting over here. So what? They're both old and slow, and neither has the processor power to justify a fan.
That was then...
Now the iMac, iBook and PowerBook all have fans. And Power Macs now have 3 fans!!!
So much for the silent office...
If you want an almost silent fan, check these out. Very cool.
This fan seems to have both advantages and disadvantages. The most obvious for me advantage is that its axis vibrates less -- force is applied to the edges of the fan, straightening it. That may help with the problem that often kills "classic" fans -- the bearing (that usually is a brass pipe attached by one end to the plastic base and a steel pin attached by the opposite end to the hub of the blades) wears out unevenly, what causes the fan's pin to roll in the pipe, and with precession causing further damage that, among other things, converts a cylindrical surface into a cone, making a bad problem even worse, causing more noise, vibration, squeezing out the lubricant and clogging of the bearing.
;-).
Another positive thing is that this design (but not the device itself) allows for relatively easy improvement -- even though the picture looks like the bearing is the same as I have described above, this can be converted into a "reversed" bearing design without the motor getting in the way -- a pin can be attached to the plastic base/grille at both ends, and a pipe (or ball bearings, or whatever) -- to the middle of the hub. Then the fan will be also symmetric and even less vulnerable to the vibrations. "Classic" fan design can be converted into this, however then the rotating pipe would push back already tiny coils and cores of the motor. With coils outside, and reduced vibrations in the first place this would be more efficient (and oh, btw, if some asshole will try to patent this, I would be happy to see him in court, with this comment as an evidence of the prior art
The disadvantages are also obvious. First, blades, even with heavy magnet ring on their ends, are still flexible and prone to deformation. This may affect the balance of the rotor in the long run -- "classic" fan has a smaller ring magnet in a sturdy plastic cup of the hub, and therefore is almost invulnerable to this (until the bearing wears out enough to shift the center -- but by then the fan would be dead already). Second, this, and plain need to accommodate heat expansion, precision of manufacturing, etc. increases the necessary gap between magnets and cores. That would require larger, stronger coils, but there isn't that much space available for them in the corners.
Contrary to the popular belief, there indeed is no God.
Glad you're not an engineer.
I thought of this concept a while back, even started modelling it in Simulink (part of Matlab).
"First, the velocity of the blades near the hub are too slow to put work into the air and therefore the air tends to leak backwards near the hub. This is why putting the motor in the hub area does not degrade fan performance."
First of all, the hub is smaller, meaning the there is more air intake near the hub...anything which calls for a greater air debit at the top of the fan is good. The air will only 'leak back' if the air pressure under th fan is greater than on top, which doesn't happen until you hit high RPM's. What you will get is vortices under the fan near the hub, which is good...it means a lot of airflow over the die of the chip, which leads to cooling of the chip. Note that this happens under the fan, which is where you do want vortices.
"Second, while the fastest parts of the fan (the blade tips) make most of the fan noise, changing their shape does the most to reduce the noise. The noise has nothing to do with the "motor parts" that reside in the blade tips in this design."
The thing is, the tips of the blades are in the ring surrounding the fan...now the air first gets led through a bounding area before it gets spun by the fan...it goes from vertical to horizontal directly, like in any good pump, without having that airflow distorted by the boundary conditions created by the tips of the fan being near but not touching the side of the fan case. Vortices on top of the fan only make for a decrease in airintake which is bad for cooling.
"Third, the pressure generated by the fan is solely dependant on the fan design and has nothing to do with how the fan is powered."
But here the method of powering the fan has led to an improvement in fan design (more air intake due to higher area of the fanblades).
"Fourth, of course the torque is more effective at a larger radius, but this has nothing to do with efficiency."
Thiuss hasd no bearing on the situation other than stating that the larger a fan is, the better it works...duh, we already knew that.
"Fifth, any increase in air flow has to do with the shape of the blades and the speed of the fan and can probably be improved a somewhat by blocking the hub a little."
No, that would only limit the area of air-intake, which is bad...you want a big area of intake, to get as much air down the fan as possible. Blocking the hub is a Bad Idea(tm)
"Sixth, I do not see how the fan improves the efficiency of cooling anything. Increased air flow will cool anything better, according to how much horsepower do you want to put into your fan. And, it matters a whole lot where the parts to be cooled are in relation to the exit air stream, etc.etc.etc."
Yeah, you got the idea...this new design improves airflow, which is good!
Not PR, just airflow...they increase the airintake (by having a smaller hub, which also means better cooling near the centre of the fan) while lowering vortices near the airintake (by having a seamless fancase-fan interface), thus creating better cooling.
sleeve bearing is much quieter than ball bearing but coolers using sleeve bearing don't live very long.
some papst fans use sintec sleeve bearing with ceramic sleeves - they are most quiet fans and life nearly as long as ball beared ones.
it is also better to take bigger fans for they are more efficient and can achiefe the same airflow als smaller fans but with lower rpms.
i humbly suggest to use a papst 8412 ngl fan - it is the quietest fan in that size, although not cheap.
the problem with the center of the heatsing being not cooled properly because of the motor in the middle of the fan can be solved quite easily - put the fan a bit higher.
"It's such a fine line between stupid and clever" -- David St. Hubbins, Spinal Tap
The PC fan's lack of reliability is the cheapness of the brushings - nothing to do with what's in the middle. Typically most cheap fans fail because
;)
there is slack in the Z axis causing it to rattle. A single washer of the right thickness is all that's needed to keep the fans running for the next few years.
FYI: The regular PC fan (as well as floppy) is driven by a brushless DC motor. The fan blade in the middle has a magnet. Solid state magnetic sensor(s) are used to fire electromagnets around it in sequence creating a rotating magnetic field. This is sort of like a rail gun except it goes round & round.
one thing I noticed that was really smart about a little dell optiplex we have is the fan.. it has a 3" squirlcage fan.. like you have in most home forced-air heating/ac systems.. or range hoods. it's very quiet, and moves a signifigant ammount of air.. like someone posted earlier.. the blades in the center move slowly, and the blades at the edge move fast, so you don't get an major advantage to having the motor on the outside. with a squirlcage fan, all the blades are on the outside, moving at the same speed. now just combind that with variable speed cooling.. and things will be very good.