Physical questions

[Joel Jaeggli]

On Wed, 15 Jan 2003, Ray Muno wrote:

> Liebert has an interesting solution for high density rack cooling. They 
> call it RackCooler.
> 
> http://www.liebert.com/dynamic/displayproduct.asp?id=1037&cycles=60hz
> 
> They are designed to remove 8kW per rack on the exit side, before it enters 
> the room allowing the central system the ability to maintain the general 
> room temperature and eliminate some of the heat in the "hot aisle". 

I sort of loath the idea of moving coolant around in machine rooms even 
when it not electrically conductive, more pumps more hoses, we have enough 
problems dealing with our primary and backup chilled water sources. 

In the new racks on our telco facilty they've installed seperate air 
ahndlers for each set of racks.

joelja
 
> On Tue, Jan 14, 2003 at 06:19:42PM -0500, Robert G. Brown wrote:
> > On Tue, 14 Jan 2003, Michael Stein wrote:
> > 
> > > > High density clusters also carry a fire risk of their very own.  One can
> > > > easily achieve node densities that consume 2 or 3 thousand watts in a
> > > > rack (and with effort, can maybe double that).
> > > 
> > > I've seen a dual 2.4 GHz Xeon Intel 1U machine measured at 250 W (multiple
> > > "burn*" running).  A rack full of these (42 U) really is 10KW.
> > 
> > Has anyone actually filled a rack with nodes this hot and burned this
> > much power, per node, sustained?  Kind of scary, if you have;-)
> > 
> > A joule is dropping a one kilogram hammer on your finger from 10 cm.
> > 
> > So 10KW is a one-metric-ton jackhammer, pounding up and down one meter
> > once a second, sustained.  With all the cooling fans running, it
> > probably sounds like one as well...:-)
> > 
> > Ouch!
> > 
> >    rgb
> > 
> > -- 
> > Robert G. Brown	                       http://www.phy.duke.edu/~rgb/
> > Duke University Dept. of Physics, Box 90305
> > Durham, N.C. 27708-0305
> > Phone: 1-919-660-2567  Fax: 919-660-2525     email:rgb at phy.duke.edu
> > 
> > 
> > 
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> =============================================================================
>  
>  Ray Muno                           http://www.aem.umn.edu/people/staff/muno
>  University of Minnesota                          e-mail:   muno at aem.umn.edu
>  Aerospace Engineering and Mechanics               Phone:     (612) 625-9531
>  110 Union St. S.E.		                     FAX:     (612) 626-1558
>  Minneapolis, Mn 55455			
> 
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Joel Jaeggli	      Academic User Services   joelja at darkwing.uoregon.edu    
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