Re: FreeAxez raised flooring?

[Tim Durack <tdurack () gmail com>]

> > We have/are building new datacenters with a raised floor plenum. Air
> > is directed into the racks from below, and ducted out of the top. No
> > hot/cold aisle, just lots of cold air to cool the equipment. It's an
> > AFCO rack design. Seems to be efficient so far.
>
> How do you measure efficiency?  How do you blow air on all the
> computers in the rack and not just the bottom one?
>
> Hot/cold aisles are going to be way more efficient, or at least more
> uniform.  Your systems are probably like most rack mount gear and
> designed to take air in the front, route it over the internals in an
> ideal way (possibly using baffles) and spitting it out through the
> back.  Hot/cold aisles work with this system.  Your way hits the bottom
> box and then spits the air out of the rack missing the top systems.

Same way you cool the top of a rack in a cold/hot aisle system. Blow
cold air up the front of the rack. We measure temperature at select
points in the rack. Keep the hottest spot below set point, and
everything is fine. The physics aren't that much different.

We are cooling 20kw per rack with this setup. 4 hp c-class chassis per
rack. Works great.

-- 
Tim:>