Data Center Expansion Modeling - Yahoo!, La Vista, NE

Category: Data Center

Square Footage: 79,000 sq ft

Services Provided: HVAC, Plumbing, Process Piping

Completion Date: 2014

Owner: Yahoo!

Architect: Jackson Main Architecture

General Contractor: DPR Construction

Mechanical Contractor: The Waldinger Corporation

Electrical Contractor: Cupertino Electric

The first Yahoo data center in Nebraska, NE1, needed to be doubled in size from 9-megaWatts to 18-megaWatts. Yahoo hired Pragmatic PE to engineer the mechanical drawings, develop CFD models, and perform thermal runaway calculations. The cooling system was a combination of indirect and direct evaporative coolers as the first stage and chilled water coils as the second stage. The chilled water coils were located within the white space as part of the customized racks.

During design, a question arose as to whether the MDF racks, centrally located between the contained aisle pods, would need to be curtained off. Pragmatic PE performed a CFD analysis and the results showed that indeed curtains were recommended. The upper graphic shows the MDF rack close-up without curtains and the lower graphic shows the same area at the same elevation above the floor with curtains. Note how the upper graphic has heat pollution migrating from the MDF area into contained aisle pods which was unacceptable to the client. As a result of this investigation, the MDF aisles were fitted with curtains to maintain cooling integrity at the servers.

Pragmatic PE developed two contained aisle modules with separate sequences of operation because half were low density racks and the other half were high density racks. This project is another example of Pragmatic PE ingenuity fulfilling the needs of customized data centers.