DATA CENTER AIR MANAGEMENT

Data center energy consumption has continued to grow due to the increasing intensity with which businesses and individuals use IT. Traditional cooling systems in legacy data centers supply cold air from computer room air handling (CRAH) units located on the perimeter of the room to IT equipment via a raised floor. Cooling units deliver cooled air to the data hall; these are usually chilled water CRAH units, direct expansion computer room air conditioning units, or air handling units. The authors use four characteristic temperatures in each data hall: cooling unit and IT equipment inlet and outlet, to calculate bypass, recirculation, flow availability, and air segregation by applying mass flow balance equations. Each hall has only one set of these metrics. Air containment helps to segregate hot and cold airstreams and limits the opportunities for bypass and recirculation, providing opportunity to only supply the necessary airflow and to raise cooling unit set points.