Using Jet Engines to Cool Servers

rpmsci writes "The computer servers that fill huge data centers are producing more heat with every new generation of processors. It's a problem that's sending engineers on a search for cooling fans that are both small enough to fit inside ever-smaller server chassis and powerful enough to dispel increasing amounts of heat. At Hewlett-Packard, they've found one answer in an unexpected place: model jet airplanes."

Comments

Too Late

[AKAImBatman]

ASUS beat them to it

Re:Too Late

[Walt Dismal]

This of course leads to the obligatory lines, "Thank you for flying with HP Airlines. I'm Miss Goodbint, and I'll be your data server on this flight. Please ignore the vast sucking noises coming from the rack, they're normal. In the event of a loss of cabin pressure, strange little yellow masks will pop out of the equipment so your data center technicians don't asphyxiate."

Not a jet.

[LWATCDR]

These are just ducted fans. There are actually tiny gas turbine engines available for model aircraft.
I have to wonder how much if this is really just hype. Last time I looked at my cooling fan it was already a ducted fan.
Are they adding extra stages? Maybe more an more efficient airfoil on the fan blades? Longer duct? Higher RPM?
I find this a huge so what.

Re:Not a jet.

[scdeimos]

You mean "used to be available". Have you tried to order these after 9/11?

Yes, there's virtually no difference in availability:

• AMT - Advanced Micro Turbines
• ARTES Jet
• Behotec
• BMT - Baird Micro Turbines
• Jakadofsky Jet Engines
• JetCat USA
• SimJet
• SWB Turbines
• TJT Australia
• Wren Turbines

And there's a whole bunch more here. There's no shortage of gas turbine planes and pilots in our aeroclub, either.

Christ, is "active" a hip marketing term again?

[xxxJonBoyxxx]

"The end product is HP's Active Cool Fan..."

Christ, is "active" a hip marketing term again? I thought "ActiveX" put a bullet in that fad...

Re:Christ, is "active" a hip marketing term again?

[gEvil (beta)]

Well, it certainly isn't a passive cooling solution...

Why bother?

[RingDev]

Air is such a poor heat transfer medium. Why not build a rack with a water cooling system built in? I have an external water cooled solution on my home PC connected via a set of no-break quick release couplings. So any time I need to pull my PC apart I can pop the coolant lines with out losing a drop of coolant or introducing air into the system.

I can't imaging running a fleet of model airplane engines is going to be quite, cheap, or all that reliable. Especially when compared to an rack integrated water cooling system.

-Rick

Re:Why bother?

[harrkev]

This is not my field, but I would imagine that it would be because business are averse to risk. Fans are known and reliable. Watercooling is new and unknown in a 19" rack. What if YOU were the first one to suggest installing it, and it leaked? Bye bye job.

If an enthusiast's system leaks, he misses the next LAN party. If it happend on the top computer on a rack, that system goes down. The water then trickes down to the next lower computer and destroys it. Maybe the water will go down to the next computer under that.

I do admit that some clever engineering to put drain pans leading to drain hoses can connect to a bucket on the floor. But, somehow, I can't imagine too many business buying that.

Re:Why bother?

[caffeinatedOnline]

I don't know much about in a rack system, but I had been running a Big Water system in my gaming rig for about a year, and it developed a slow leak. Mind you, they recommend that you check the fittings every so often for leaks, which is something that I didn't do as religiously as I should have. I had modified it by including 2 VGA coolers, and a leak developed on one of the VGA coolers and a smaller leak on the CPU block.

The leak from the CPU block was such a small leak that it dripped sludge, as the water evaporated before it could actually drip, and the residues built up. Unfortunately, the sludge landed right on the back of one of the video cards, on the GPU connections. Crossfire didn't much appreciate the signals that the video card was sending, and pretty much fried both cards and the PCI-e slots on the motherboard.

The leak from the VGA block dripped on my audio card, and fried that. In the end, I ended up having to replace 2 video cards, an audio card, motherboard, and a 1 gig stick of ram (fried as well, but can't be sure that it was caused by the water.) I can imagine that a leak in a rack would be even more catastrophic.

Re:Why bother?

[SatanicPuppy]

Might want to try some Fluid XP coolant. It's non-conductive, so no zapped parts. It's non-corrosive, so fewer motor problems. And it's non-toxic, so if your 2-year old glugs a quart of it, all they get is blue teeth.

I've never heard anything bad about it, and it works fine for me.

I like this better...

[AgentAce]

http://www.asciimation.co.nz/beer/

Yeah, real innovative HP. *yawn*

Not the same thing

[linuxkrn]

That asus is just a standard fan mounted in a case that looks like a jet engine, but it's the same technology.

On the other hand, the HP one uses small blades that are shorter and that spin faster. As such they create more thrust/airflow and reduce noise that normal blades produce from the tips of their blades.

RTFA, it's got a good discription, yeah, I know it's /. but sometimes it's worth reading.

Melted plastic and metal everywhere

[blueZ3]

Sheesh, Zonk -- could we at least take, say, three seconds to think before writing the article title. How about "Using jet engine technology..." instead of "Using jet engines..."

Little clue: Jet exhaust is... well, let's just call it "a little warm for cooling a server" and leave it at that. The article title gave me this picture of a Rolls jet engine (http://www.rolls-royce.com/education/schools/how_ things_work/default.jsp) sucking JP4 and blowing 1000's of cubic feet per second of very hot air into the server room here at work.

Oh the humanity!

Drat

[hcdejong]

For a moment I thought they were using actual jet engines to cool the server, but noooooo, they had to go for boring ol' electric fans instead.

[insert rant about misleading summary]

Hard Lesson

[Gr8Apes]

That's a hard lesson learned there, spend the $35 for a non-conductive liquid and save hundreds, if not thousands in hardware costs. The same thing applies to UPSes.

A way to use a real jet engine

[necro81]

Since these ducted fan's aren't really jet engines, and certainly aren't what I had in mind when I saw the term "jet engine" in the headline (think very large and noisy!), here's a proposal for using a real, full-sized, jet engine for cooling your servers:

Take one jet engine,
Add stages to capture the thrust and transform it into more torque,
Connect output shaft to massive freakin' compressor turbine,
Use turbine to compress gaseous coolant back to a liquid,
Attach big large radiator/heat exchanger/water cooling tower

Viola! you now have many tonnes of refrigeration capacity, good for blowing cold air through your equipment room, or circulating liquid coolant directly to the chips.

The best part is, you get to have a jet engine tacked on to your server farm.

Liquid cooling with HVAC chilled water

[Kadin2048]

Actually most datacenters already have massive water-cooling systems: only they're building wide and generally used to cool the air. I'm talking about the HVAC system, of course.

Large buildings generally don't circulate Freon from one floor to another, it would be too expensive. Instead, they have a big refrigeration unit (roof mounted, usually) with big cooling towers and the rest, and use it to chill water, which is pumped throughout the building and used to cool air.

It wouldn't be very difficult to tap into the chilled-water lines that already exist in most buildings, and use them to cool the servers directly. In fact this was once a lot more common: back in the day, it wasn't uncommon for big mainframes to be water-cooled. I've worked with big scientific apparatus that's also water-cooled, and a lot of it used lots of electricity as well, so it's not as though the engineering is impossible.

Yes, there are certain risks associated with having water flow through your computer system, especially in regards to leaks. But there are lots of pieces of equipment that contain liquid and wouldn't appreciate leaks, and we don't think twice about them. For very valuable systems, an additional cooling loop filled with a non-conductive (or even better, a pressurized gas) coolant could be used, with a heat exchanger connecting to the building chilled water.

I think there are some IBM blade systems out there right now that use liquid cooling, but for some dumb reason they won't accept building chilled-water connections (believe it or not, they need water that's warmer than most building supplies). I can't find a link to it right now, but basically it introduces an additional heat exchanger for the sole purpose of warming the incoming chilled water supply before circulating it through the systems. Obviously, this limits their attractiveness and ease of installation.

But at any rate, I think going to liquid cooling, whether water or glycol or something else, is eventually inevitable in high-density applications: despite some of the practical problems involved, when you look at the economics, cooling is one of those things that scales really well. It's going to be cheaper in the long run to reduce the number of heat-transfer steps in between the chip and the outside environment (where the heat is going one way or another), and to do it all at once if possible. Maybe we haven't hit the power/density break-even point yet, but we must be getting close.

I think the reason you still see a lot of air-cooling is because the mass-production of components has made it inexpensive to do, but blade server systems are starting to run into the limits of commodity hardware (as this whole story with HP's fan attests to). When you start having to consider developing specialized cooling hardware anyway, whether for air or liquid, suddenly liquid cooling becomes more attractive.

Until it lands in the dust

[A nonymous Coward]

Won't it then become conductive, or rather the mixture of wet dust?

How they work.

[twitter]

On the other hand, the HP one uses small blades that are shorter and that spin faster. As such they create more thrust/airflow and reduce noise that normal blades produce from the tips of their blades.

That's about all the article says.

The key ingredient to a ducted fan is efficient expansion. Any old array of twisted parts can propell air. I read another article and fabricated such a thing from Dixie cups. After your rotor comes the stator, a very important component missing from ordinary fans, which removes the angular component of the flow velocity. You want to move the air down your axis not around it. Getting the air moving along the axis and expanding it out to larger volumes without wasting your effort is hard to do. Adding any stator will help. Doing it quietly and efficiently is one of those rocket science things.

Wikipedia, of course, has a quick article,

and Google turns up an easy design text.