EVALUATION OF COOLING ARCHITECTURES AND CONTROL STRATEGIES IN AIRFLOW PROVISIONING A MODULAR DATA CENTER

Abstract

To achieve energy efficiency and reduce operational costs in data centers with modularized Information Technology and cooling infrastructure there is an ongoing trend to minimize the use of mechanical cooling and instead use outdoor air in favorable environmental conditions for cooling purposes. The cooling module can comprise of evaporative cooling systems which use direct, indirect or a combination of direct/indirect evaporative cooling units to provide adequate cooling. The degree of cooling achieved in the IT module depends on the effective airflow provisioned and the air distribution methods employed. In this study, a modular data center which is equipped with a direct/indirect evaporative cooling unit is considered. The IT module consists of a row of four 42U racks populated with 1U web servers. The conditioned air is supplied through a ducted vent flooding into the cold aisle and the return hot air is exhausted out when not necessary and utilized for mixing purposes otherwise when operating in economizer mode. Commercial CFD tool- 6SigmaRoom is used to develop a CFD model of modular data center and validated with existing research facility in Dallas, TX. To ensure adequate airflow provisioning, a comparison of temperature-based and pressure differential based measurements in IT module is carried out to control the supply fans in the cooling module. Also, different cooling architectures are studied to determine the impact on thermal performance and efficiency of the cooling solution. The results shall be used to optimize the air distribution on existing research data center facility.