TY - GEN
T1 - From chip to cooling tower data center modeling
T2 - ASME/JSME 2011 8th Thermal Engineering Joint Conference, AJTEC 2011
AU - Breen, Thomas J.
AU - Walsh, Ed J.
AU - Punch, Jeff
AU - Shah, Amip J.
AU - Bash, Cullen E.
AU - Rubenstein, Brandon
AU - Heath, Scot
AU - Kumari, Niru
PY - 2011
Y1 - 2011
N2 - In the drive to enhance data center energy efficiency, much attention has been placed on the prospect of airflow containment in hot-aisle cold-aisle raised floor arrangements. Such containment prevents airflow recirculation, eliminating the mixing effects of the hot and cold air streams that can cause an undesirable temperature rise at the inlet of the equipment racks. The intuitive assessment of the industry has been that the elimination of such mixing effects increases the energy efficiency of the data center cooling system by enabling delivery of air at higher inlet temperatures, thus reducing the amount of infrastructure cooling required. This paper employs an end-to-end modeling approach to analyze the effect of air stream containment in the computer room and its impact on the holistic system efficiency. Dimensionless heat index parameters are employed to characterize the effects of containment, recirculation and mixing within the computer room environment. The extent of recirculation is shown to primarily influence the operation of the rack and CRAC level cooling systems, with the chiller systems also impacted. The overall effect on the complete cooling system performance and data center efficiency requires balancing of these effects. Through this model analysis, it is shown that containment may negatively impact overall energy efficiency in some circumstances, and that recirculation may actually be beneficial to overall energy efficiency under certain system dependent operating thresholds.
AB - In the drive to enhance data center energy efficiency, much attention has been placed on the prospect of airflow containment in hot-aisle cold-aisle raised floor arrangements. Such containment prevents airflow recirculation, eliminating the mixing effects of the hot and cold air streams that can cause an undesirable temperature rise at the inlet of the equipment racks. The intuitive assessment of the industry has been that the elimination of such mixing effects increases the energy efficiency of the data center cooling system by enabling delivery of air at higher inlet temperatures, thus reducing the amount of infrastructure cooling required. This paper employs an end-to-end modeling approach to analyze the effect of air stream containment in the computer room and its impact on the holistic system efficiency. Dimensionless heat index parameters are employed to characterize the effects of containment, recirculation and mixing within the computer room environment. The extent of recirculation is shown to primarily influence the operation of the rack and CRAC level cooling systems, with the chiller systems also impacted. The overall effect on the complete cooling system performance and data center efficiency requires balancing of these effects. Through this model analysis, it is shown that containment may negatively impact overall energy efficiency in some circumstances, and that recirculation may actually be beneficial to overall energy efficiency under certain system dependent operating thresholds.
UR - http://www.scopus.com/inward/record.url?scp=85088715336&partnerID=8YFLogxK
U2 - 10.1115/ajtec2011-44091
DO - 10.1115/ajtec2011-44091
M3 - Conference contribution
AN - SCOPUS:85088715336
SN - 9780791838921
T3 - ASME/JSME 2011 8th Thermal Engineering Joint Conference, AJTEC 2011
BT - ASME/JSME 2011 8th Thermal Engineering Joint Conference, AJTEC 2011
PB - American Society of Mechanical Engineers
Y2 - 13 March 2011 through 17 March 2011
ER -