I have recently written about the relationship of CFM and cooling.
Most of the arguments in the industry about using slab floor instead of raised floor are effectively cooling higher density payloads beyond 4kW/rack. And that is a very low payload in today’s context.
The picture on the left is an example of a data center on slab floor (this is Sun’s Santa Clara data center). The theory behind cooling such a facility is to bring the cooling closer to the heat source and deliver it horizontally (row-based) or vertically (rack-based), instead of distributing over the sub-floor.
