Supporting the Stockpile Stewardship Program at LLNL
WCI uses the following cutting-edge facilities in conducting its mission to ensure the safety, reliability, and security of the U.S. nuclear stockpile without nuclear testing, develop advanced manufacturing and materials technologies to maintain our nation's stockpile, and to ensure the safe dismantlement of retired weapons.
The National Ignition Facility (NIF), the world's largest and highest-energy laser, was dedicated on May 29, 2009. In 2010, NIF began experiments that focus the energy of 192 giant laser beams on a BB-sized target filled with hydrogen fuel. NIF is capable of creating temperatures and pressures similar to those that exist only in the cores of stars and giant planets and inside nuclear weapons. Achieving nuclear fusion in the laboratory is at the heart of our mission to help ensure the nation´s security without nuclear-weapons testing. NIF is the only facility that can perform controlled, experimental studies of thermonuclear burn, the phenomenon that gives rise to the immense energy of modern nuclear weapons. It provides unprecedented experimental access to the physics of nuclear weapons. Data from NIF experiments complement testing at other experimental facilities at Livermore and elsewhere. This experimental data helps to inform and validate sophisticated, three-dimensional weapons-simulation computer codes and bring about a fuller understanding of important weapon physics.
The High
Explosives Applications Facility (HEAF) is a DOE/NNSA complex-wide Center of Excellence for high-explosives research and development. Research at HEAF includes the development of new explosives in the synthesis and formulation laboratories, explosives properties testing, hydrotest and diagnostic development, diamond-anvil experiments for basic explosives-properties research, a microdetonics laboratory for explosives studies at the micron scale, and multiple firing tanks for explosives testing at larger scales.
HEAF has seven large fully contained firing tanks for testing explosive quantities from less than a gram up to 10 kilograms (22 pounds). The facility also has a 100-mm research gun that fires into a specially designed tank for high-velocity-impact studies.
The Terascale
Simulation Facility (TSF) houses two of the world's fastest supercomputers—BlueGene/L and ASC Purple. These amazing machines, which perform trillions of operations per second (teraFLOPS), support an important component of stockpile stewardship. The supercomputers reside in the two computer rooms dominating the second level of the two-story supercomputer wing. The west room houses Purple, and the east houses BlueGene/L.
Key stockpile-stewardship-application results on BlueGene/L are pointing to a qualitative change in the way computational science can be performed. BlueGene/L is optimized to run molecular-dynamics applications at extreme speeds to address materials-aging issues confronting the Stockpile Stewardship Program. The Advanced Simulation and Computing (ASC) Program's Purple system is used to develop complex three-dimensional integrated weapons performance applications. Sequoia is expected to be the most powerful supercomputer in the world and will be focused on strengthening the foundations of predictive simulation by running very large suites of complex simulations for uncertainty quantification (UQ) studies. In addition, the machines will be used for weapons-science calculations necessary to build more accurate physical models. This work is a cornerstone of NNSA's Stockpile Stewardship program to ensure the safety, security, and reliability of the U.S. nuclear-weapons stockpile today and into the future without underground testing.
Site 300 is comprised of 7,000 acres in the foothills 15 miles southeast of the Lawrence Livermore National Laboratory (LLNL) and was established in 1955 for explosives testing. Site 300 supports the Laboratory's nuclear-weapons research and development (R&D) program by assessing the operation of nonnuclear weapon components through hydrodynamic testing using high explosives. The WCI Directorate's B Program uses advanced diagnostics such as high-speed optics and x-ray radiography to compare the phases of the hydrodynamic flow from nonnuclear high-explosive experiments with computational data in order to assess the performance of the component.
The Contained Firing Facility (CFF) at Site 300 is an important tool for diagnosing the high-energy prenuclear phase of nuclear weapons. CFF is the only contained firing facililty (unlike other uncontained facilities such as DAHRT). In addition to testing hydrodynamic behavior of parts, CFF is used to assess weapons surety and vulnerabilities.