[Beowulf] Helium-filled hard disks

[Robert G. Brown]

On Mon, 17 Sep 2012, Gus Correa wrote:

> Tangentially related to the recent discussion
> of server/data center cooling with Helium [and Helium depletion]:

Thanks.  Actually, very interesting.  Lower drag (lower viscosity) makes
sense.  Helium should also be a substantially better conductor of heat
from the platter to the outer disk casing and eventual loss mechanisms
in the case.  The other issue they refer to -- sealing the space -- is
nontrivial.  Helium is small enough that even metals are subject to
diffusion, especially if you have hotter helium on the inside -- and
very likely to embrittlement as time passes and more helium diffuses
into (and through) the metal, creating lattice defects.  I'm curious as
to whether they wrap the sealed volume in e.g. lead foil or some other
comparatively dense metal.

     rgb

>
> https://www.computerworld.com/s/article/9231220/Helium_filled_WD_drives_promise_huge_boost_in_capacity?taxonomyId=19&pageNumber=1
>
> http://arstechnica.com/information-technology/2012/09/helium-filled-hard-disks-will-lead-to-higher-capacities/
> _______________________________________________
> Beowulf mailing list, Beowulf at beowulf.org sponsored by Penguin Computing
> To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
>

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