The thermal loads possible with a new IBM supercomputer can be effectively simulated using CFD software, allowing engineers to effective plan the supercomputer's environment.

Engineers from CH2M Hill use the Flovent airflow simulation software, a computational fluid dynamics (CFD) solution, to simulate predicted thermal loads that will be generated by IBM’s RoadRunner machine. The RoadRunner supercomputer will be capable of a sustained speed of up to 1,000 trillion calculations per second, or one petaflow, and will use 16,000 Cell B.E. processors and 16,000 AMD Opteron processor cores. Installed at Department of Energy’s Los Alamos National Laboratory’s Nicholas Metropolis Center, the supercomputer will primarily be used for simulations to ensure the safety and reliability of the nation’s nuclear weapons stockpile. Flovent is marketed by Marlborough, Mass.-based Flomerics.

One of the key challenges of owning and operating this enormous computing resource is addressing the critical thermal management challenges. A conventional data center is composed of racks that typically dissipate between 2 and 6 kW. By comparison, the high-density racks in the Metropolis Center dissipate up to 20 kW per rack.

CH2M Hill was contracted several years ago to perform thermal simulation as part of the planning for the installation of Roadrunner, as well as other expansion projects in the Center. By regularly modeling the facility, engineers have helped the DOE stay one step ahead of the continuously increasing thermal load while minimizing initial and operating costs of the cooling equipment.

“The CFD simulations have saved money by determining exactly how much cooling capacity is required to handle current and projected thermal loads and identifying design improvements that boost cooling efficiency,” says Andy Solberg, CH2M Hill engineer.