While Teradata strongly recommends a raised floor environment, non-raised floor environments do exist, specifically those using the overhead cold air delivery method. In a raised floor environment, cold air is delivered from bottom to top, and warm exhaust air rises and tends to stay close to the ceiling. Overhead cold air delivery is more complex and less efficient due to the potential of downward flowing cold air mixing with rising warm exhaust air.
The following figure shows the recommended locations of cold air diffusers and return vents. Placement of diffusers is not flexible, as it is with vented tiles. However, the physics remain the same. The cooling capacity offered by A/C handlers must be sufficient to remove heat generated by hardware equipment, with considerations given to heat removal inefficiency.