Idaho National LaboratoryCoordinator: Mark DeHart
Idaho National Laboratory (INL) is a multiprogram science and engineering laboratory operated for the U.S. Department of Energy. With more than 3,500 scientists, engineers and support personnel, INL has been designated as the nation’s lead laboratory for advanced civilian nuclear technology research and development and performs work in each of the Department of Energy’s four strategic goal areas; energy, security, environment, and science. It is home to one of the largest concentrations of technical professionals in the northern Rocky Mountain region, split between the INL “site” that covers 889 square miles of the Snake River Plain west of Idaho Falls, Idaho and various offices and laboratories located within the city. INL has been a leader in new reactor designs and fuel reprocessing and fabrication for over 50 years, and has constructed more than 52 reactors within its borders.
Computational science research at INL focuses on applications within nuclear energy, national security, and science and technology. These efforts range from developing new numerical algorithms to developing scalable parallel multiphysics software applications for the design and analysis of reactor fuels. This research is spread across various groups and research teams, a few of which are described below.
Computational Nuclear Science
INL is developing a variety of design and analysis capabilities to support the Laboratory’s mission in computational nuclear engineering (see http://www.inl.gov/featurestories/2008-01-02.shtml). Specific topics include general solutions to various physics coupling issues found inside the reactor core, the development of better approaches to couple mesh h-, r-, and p-adaptation and alignment with multiphysics error indicators, work in dynamic sensitivity analysis, and applying advanced computational methods to diverse problems in nuclear science and technology.
The Multiphysics Methods Group at INL has a number of research projects in which fellowship students could participate. The group’s mission is to advance the state of computational nuclear science and engineering through advanced computing. Current research topics underway in the group include:
- Mesh generation/adaptation on complex reactor systems
- Parallel applications software development
- Robust parallel nonlinear solvers
- Advanced finite element methods for fuel contact and cracking
- Scientific visualization
- Computational two-phase fluid flow
- Validation, verification, and uncertainty quantification methods and processes
These projects cover a broad range of scientific and engineering disciplines and represent exceptional challenges for applied research on advanced computers. For a snapshot of other activities of the group, Google the "Multiphysics Methods Group".
The Reactor Physics Methods Group at INL is developing algorithms and methods to support computational reactor and radiation physics applications. Major focus areas of the group include the development of methods for high-temperature gas reactor (HTGR) analysis, nuclear fuel cycle analysis for the Global Nuclear Energy Partnership (GNEP) program, as well as:
- Physics support of Advanced Test Reactor (ATR) experiments
- Advanced reactor modeling
- Computational reactor physics methods development and benchmarking
- Nuclear criticality safety
- Medical applications of nuclear science
INL has other challenging opportunities ranging from computational material science research and development to environmental science; including topics in computational mathematics, energy and subsurface sciences, and the development of large software systems. Examples of specific projects include:
Reactor Fuel Performance
INL is developing a modern, multiphysics software architecture to predict the degradation of reactor fuel over time, with the goal of optimizing the design of fuel rods to maximize their life and the development of reactor operating procedures that minimize the buildup of fission byproducts. The ultimate objective is to use a fuel rod for a longer period of time before it needs replacement, reducing both the cost of electricity produced by the generation facility and the amount of waste created per kilowatt-hour of power generated. Development of this code requires advanced methods for solving coupled partial differential equation systems that describe multidimensional fuel thermo-mechanics, contact between the fuel and protective cladding, heat generation and transport within the fuel, chemical constituent and porosity migration, fission product generation and migration, fuel structural degradation, radiation damage, and corrosion. While these equation systems may be closed using experimental data; in the near future advanced numerical methods, goal-oriented adaptation, and higher-order discretization methods will combine with new computing hardware to allow macro- and microscale models to be dynamically-coupled to the engineering scale calculation, along with the use of sensitivity analysis to predict the importance of various design parameters to the fuel’s lifetime. This project provides a range of opportunities from interacting with fuels modeling experts and data collected at the INL Materials and Fuels Complex to working on the leadership computing platforms at INL and across the DOE laboratory complex.
Multidimensional Reactor Core Modeling
INL is developing the capability to perform parallel multidimensional core simulation in support of reactor design and analysis. This work involves the development of new mesh generation technologies and software that faithfully resolve the complex geometry and physics inside a reactor vessel and that meets the requirements of the multiphysics code using the mesh. This effort will also develop goal-oriented adaptive methods to support coupled multiphysics simulation of coolant flow, boiling, neutronics, heat transfer, structural response and vibration, corrosion and crud buildup, and that couples to fuel performance analysis capabilities.
Reactor Thermal Systems Analysis
RELAP5, developed at INL, is the world’s most widely used thermal-hydraulics code, with application to both light water reactor designs and advanced Generation IV reactors. RELAP5 is also used in conjunction with computational fluid dynamics (CFD), fuel performance, and reactor physics software to analyze the behavior of the Next Generation Nuclear Plant (NGNP) very high temperature reactor (VHTR) and also the liquid-metal fast reactor candidate presently being considered for the Fission Surface Power (FSP) system for the Lunar and Martian outpost power generation. Research is underway at INL to develop advanced two-phase flow methods ranging from the engineering scale to direct numerical simulation of interface evolution, as well as numerical methods to host and solve these models to predict the behavior of two-fluid systems encountered in the reactor core and cooling systems.
INL computational programs often involve a close tie with experimental programs, facilities, and expertise. Indeed, close experimental coupling is necessary for both the development of advanced computational models and the validation of those models and codes that make use of them. This relationship between experiments and computation at INL, in conjunction with the experimental expertise and unique facilities at the “site” and the Idaho Research Center (IRC), provides depth and completeness to a practicum at INL.
The Laboratory also maintains a close relationship with area universities. The Science and Technology Campus is less than a 10 minute walk from the Idaho Falls Center for Higher Education (IFCHE), where the University of Idaho and Idaho State University team to offer both undergraduate and graduate degrees in popular areas of engineering and science.