Re:Seagate Announces 12 TB HDD: 2nd-Gen Helium-Filled HDD
by astrodust on Thursday March 16, 2017 @08:23PM
(#13890351)
Why would the platters be generating heat? By definition there's no physical concact with the heads, ergo minimal friction. I thought the primary reason for using a monatomic gas was it would allow the heads to fly closer to the metal.
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Re:Seagate Announces 12 TB HDD: 2nd-Gen Helium-Filled HDD
by drivethrowinguy on Friday March 17, 2017 @06:51AM
(#13892966)
About ~3/4 of the power a drive uses goes into the spindle motor. Only a relatively small part of that is dissipated in the bearings (a quarter or so), all the rest is gas-platter friction, turbulences due to the heads etc.
Fun-fact aside: The head fly height in helium drives is ~1 nm.
Re:Seagate Announces 12 TB HDD: 2nd-Gen Helium-Filled HDD
by lutorm on Thursday March 16, 2017 @09:24PM
(#13890605)
Gases have viscosity...
Re:Seagate Announces 12 TB HDD: 2nd-Gen Helium-Filled HDD
by astrodust on Thursday March 16, 2017 @09:38PM
(#13890668)
There is that factor, but how much heat do the heads generate, that's what I'm asking.
The servo and associated electronics surely generate many orders of magintude more heat.
Re:Seagate Announces 12 TB HDD: 2nd-Gen Helium-Filled HDD
by jdietrich on Thursday March 16, 2017 @09:58PM
(#13890761)
Air shear can generate a significant amount of heat. Reducing drag will also reduce the power requirements for the motor and voice coil. HGST claim a 23% reduction in operating power over air-filled drives.
http://www.hgst.com/company/media-room/press-releases/HGST-H...
As I understand it, the crucial factor motivating helium-filled drives is the reduction of vibration due to internal turbulence. Reducing turbulence inside the drives allows platters and heads to be made thinner and packed more closely together without affecting reliability.