Cold aisle containment for server racks

The objective of this study is to optimize the cold aisle containment for a server room by means of numerical simulation, and thus to minimize energy costs by specifically optimizing the flow field. The investigation is carried out in two steps:

•  Actual condition: cold aisle containment under the complete server room space.
•  Optimized geometry: air supply as duct, optimal flow through the racks.

• Out of a total of 18 server racks, 12 are assumed to be active, with a heat output of Q = 7500W each.
• The server racks and the grid floor are not considered in detail, but were defined as porous media with the corresponding pressure loss coefficients

In both investigations, the inlet temperature is constantly defined as T = 20°C. Due to the geometry changes, a reduction of the required air mass flow by approx. 7% could be achieved. Since the air is led directly to the grille floor in the second variant, an optimum flow through the server room is achieved.

This already significantly reduces the required power consumption of the air-conditioning unit, since on the one hand less air mass flow has to be cooled and on the other hand the pump power is reduced.