Effect of server load variation on rack air flow distribution in a raised floor data center

This paper presents experimental studies on server level rack air distribution for a preset perforated tile air flow rate. A series of experiments are performed using a 22.8 kW server simulator placed in a raised floor data center facility. The rack air flow rate is varied by adjusting the fan speed of the server simulator. Particle Image Velocimetry (PIV) technique is used to capture the air flow pattern at various locations in the cold aisle at the inlet of the server simulator. The PIV images are recorded at various locations and later combined to get the complete air distribution map across the rack inlet. Various cases of rack air flow distributions are investigated by varying the server simulator fan speed settings for given perforated tile air flow rate. A significant change in the air distribution pattern is observed for various cases investigated.