Nuclear Science and Engineering

SPCA-ANL

A code to calculate consequences of sodium (or NaK) spray and pool fires
  1. Coding Language and Computing Platforms
    Fortran source code for Linux, Microsoft Windows, Macintosh
  2. Description of Purpose
    The SPCA-ANL (Spray Pool Combustion Analysis, Argonne National Laboratory version) is an engineering tool for prediction of the transient thermal/hydraulic behavior occurring as a consequence of a large-scale sodium (or NaK) leak. The model includes spray and pool burning along with the subsequent energetics associated with a leak of sodium in a building or vessel. SPCA-ANL uses a multiple-node quasi-cylindrical representation of the physical model, thus allowing the determination of local effects (Figure 1). The room is divided into several axial nodes and two radial nodes. Sodium spray is assumed to be contained within the center region, and the outer zone is denoted as the non-combustion region. The SPCA-ANL model includes treatment of the following phenomena associated with sodium fire:
    • Vertical droplet motion
    • Spray burning
    • Heat transfer between droplets and gas
    • Pool burning
    • Gas temperature and pressure
    • Venting
    • Gas circulation
    • Heat transfer between structure and gas
    • Aerosol information
Visual Representation of SPCA-ANL Model
  1. Development History
    The SPCA-ANL code is based on the SPCA-II computer code originally developed in 1980s at the Rockwell International under the Clinch River Breeder Reactor program. Under the US DOE Versatile Reactor Program, the SPCA-II code was resurrected, and modifications were introduced to the code to allow compilation by modern compilers, improve code stability, introduce new physical models, and carry out code validation based on historic spray and pool fire tests. The code was then renamed to SPCA-ANL. Since FY24, the code development is supported by the US DOE Fast Reactor Program. A Software Quality Assurance Program was preliminary developed in 2025 and was formally implemented in 2026.
  2. Code Validation
    SPCA-ANL is based on comparison of the code simulations against data from available sodium fire tests. Spray and pool fire tests from Large Test Vessel (LTV) apparatus and Containment Systems Test Facility (CSTF) tests were simulated (Figure 2).
Examples of SPCA-ANL Validation
  1. Typical Running Time
    The running time for scenarios lasting around 1 hour is generally ranging from few seconds to few minutes, depending on severity of change in conditions during sodium fires, as the code employs dynamic variation of the time step.
  2. References
  3. Primary Authors
    • A. Moisseytsev, R. Thomas, A. Brunett, Y. Zhao, M. Bucknor, T. Starkus, Argonne National Laboratory
  4. Materials Available
    The source code and compilation instructions are provided. Precompiled executables for Windows, Linux, and Macintosh are available. Documentation on methodology and installation is provided along with input and output files for the example problem. Contact Argonne’s Science and Technology Partnerships and Outreach for licensing and distribution information by emailing partners@​anl.​gov. A Software License Request Form will be required to obtain SPCA-ANL.
  5. Sponsor
    U.S. Department of Energy, Office of Nuclear Energy