Blended water-based data center cooling

A cooling system for a computer data center, comprising:

• a chilled water loop that connects loads in the computer data center with chilled water sides of one or more chillers;
• a condenser water loop that connects condenser water sides of the one or more chillers with a plurality of air-and-water radiators, where the plurality of air-and-water radiators are arranged as a grid of x rows and y columns, and each of the air-and-water radiators comprises a fin-and-tube heat exchanger and a fan mounted to circulate an airflow over the fin-and-tube heat exchanger;
• one or more fluid conduits that connect the chilled water loop to the condenser water loop;
• a common supply header in fluid communication with the chilled and condenser water loops, the common supply header circulating cooled supply water to a plurality of cooling coils positioned in airflow communication with the loads in the computer data center and receiving heat from the loads to provide heated water;
• a common return water header in fluid communication with the chilled and condenser water loops, the common return water header circulating the heated water from the plurality of cooling coils in the computer data center to provide warmed return water;
• and
• one or more control valves in the one or more conduits arranged to divide the warmed return water into relative amounts, and to route the relative amounts of the warmed return water:
• (1) from the computer data center, through a first sub-set of the air-and-water radiators, and to the chilled water loop, and (2) from the computer data center, through a second sub-set of the air-and-water radiators, and to the condenser water loop.

A cooling system for a computer data center, comprising:

• one or more chillers that define chilled water sides and condenser water sides;
• a warmed water return conduit arranged to carry warmed water from the computer data center to the cooling system;
• a plurality of air-and-water radiators arranged as a grid of x rows and y columns to receive the warmed water from the computer data center, each of the plurality of air-and-water radiators comprising a fin-and-tube heat exchanger and a fan mounted to circulate an airflow over the fin-and-tube heat exchanger, the plurality of air-and-water radiators arranged to cool the warmed water from the computer data center by circulating the warmed water through tubes of the fin-and tube heat exchangers and circulating, with the fans, ambient air around the tubes;
• a common supply header in fluid communication with the chilled and condenser water sides of the one or more chillers, the common supply header circulating cooled supply water to a plurality of cooling coils positioned in airflow communication with a plurality of computers in the computer data center and receiving heat from the plurality of computers to provide heated water;
• a common return water header in fluid communication with the chilled and condenser water sides of the one more chillers, the common return water header circulating the heated water from the plurality of cooling coils in the computer data center to provide warmed return water;
• and
• means for dividing the warmed return water into relative amounts and for controlling the relative amounts of the warmed water from the computer data center that is circulated through the air-and-water radiators and through the one or more chillers.