In this paper hard floor and raised floor cooling of servers are numerically compared. Both time-averaged and transient distributions of velocity and temperature fields are investigated with the use of computational fluid dynamics. The geometry and boundary conditions are based on Module 2 of the RISE SICS North facility located in Lulea, Sweden. Results show that for hard floor configurations, it is important to ensure that the hot air does not enter the server inlets on the return to the cooler unit. For raised floor configurations, the interplay between inlet air velocity and server fan speed should instead be considered. Flow fields further indicate that flow direction control of the outlet air in hard floor configurations and inlet air in raised floor configurations can be applied to improve the energy efficiency of the server room. Regarding transient effects, the hard floor configuration show overall larger velocity oscillations while corresponding temperature variations are comparatively small.
ISBN för värdpublikation: 978-1-5090-6684-1, 978-1-5090-6685-8