Facility Modeling & FATE Software

FAI has performed facility modeling to identify hazards across a variety of process industries, from nuclear plants and DOE facilities to chemical plants and isotope production facilities.  Our primary tool for this analysis is our FATE software, originally developed though our work for DOE legacy waste storage.  FATE™ (Facility Flow, Aerosol, Thermal, and Explosion) is a flexible, fast-running code developed and maintained by Fauske and Associates under an ASME NQA-1 compliant QA program.  

Illustration of FATE Model for a Nuclear Plant Auxiliary Building-4

FATE is a specialized tool that while it is commercially available it is primarily used to support our related safety consulting services. FATE has advanced capabilities to model heat and mass transfer, fluid behavior, and aerosol behavior in a variety of applications for the nuclear, chemical, and manufacturing sectors. FATE aerosol and transport models are universal and not restricted to nuclear or chemical release.

Read more about FATE in our white paper: FATE - A Unique Computer Code to Prevent Flammability and Explosion Hazards While Reducing Toxic Release

FATE Capabilities and Outputs

FATE phenomenological capabilities include:

  • Unlimited multiple-compartment representation, either well-mixed or stratified.
  • Generalized chemical species via property correlations
  • Arbitrary flow path network
  • Pressure-driven, counter-current, and diffusion gas flows
  • Transport of gases and aerosols between compartments
  • Vapor-aerosol equilibrium
  • Entrainment of aerosol from liquid and deposited particulate
  • Deposition of aerosols via gravitational settling, impaction, etc.
  • Combustion and detonation
  • Heat transfer and condensation on structures
  • Multidimensional heat conduction in structures
  • Heat and mass transfer between liquid pools and gas space and submerged structures
  • Special-purpose models for oxidation and Wigner energy release from graphite
  • Special-purpose models for processing of uranium metal fuel and fuel sludge

Typical outputs provided by FATE include:

  • Gas temperature
  • Pressure
  • Liquid temperature
  • Liquid elevation
  • Mass of liquid
  • Thermophysical properties
  • Gas composition in terms of mole fraction
  • Gas composition in terms of mass
  • Relative humidity of each region
  • Aerosol mass
  • Rates-of-change of gas and aerosol
  • Temperature profile in solid structures
  • Accumulated aerosol

Applications

General Industrial, Commercial, and Public Safety

  • Diesel Generator room heat buildup during a loss of ventilation event was analyzed using a FATE model.
  • The transient response of facilities during normal and off-normal conditions was applied to SARS-CoV-2 virus transmission in single-and multi-room facilities.  Under the justifiable assumptions of non-interacting virus droplets, room-wide spatially homogeneous virus droplet aerosols and droplet sedimentation in accordance with Stokes law, the FATE code tracks the virus aerosol from a human source through a facility with a practical ventilation system which reconditions, filters, and recycles the air. The results show that infection risk can be reduced by 50 percent for increased facility airflow, 70 percent for increased airflow and the inclusion of a HEPA filter on recirculated ventilation air, and nearly 90 percent for increased airflow, inclusion of a HEPA filter, and wearing a mask. These results clearly indicate that there are operational changes and engineering measures which can reduce the potential infection risk in multi-room facilities.

Chemical Industry

  • Transient model of HCl gas release in a vessel and piping system.
  • A mechanistic model of organic-nitrate reactions initiated in potentially reactive waste in underground storage tanks. A thermal-hydraulic assessment of tank transient pressure and temperature yields flows of gases to the environment, release (vaporization) of volatile materials from reacted waste, and aerosol transport and deposition provide the release to the environment.

Minerals and Metals

  • Gas generation and flow were analyzed for an ingot casting facility.  During ingot production, occasionally a break in the mold can develop, allowing the molten metal to spill out of the hardened ingot into the casting pit, producing hydrogen through the reaction of water with lithium and aluminum.

Nuclear

  • Evaluated the risk from flammable gas accumulation in buildings attached to the primary containment building. Modeled the transport and distribution/accumulation of leaked flammable gas (hydrogen and carbon monoxide) in the penetration buildings.
  • Dry cask storage (DCS) of spent nuclear fuel assemblies was analyzed for steady-state thermal behavior in an isolated loss-of-flow condition. The thermal analysis assures that the peak cladding temperature remains below the regulatory limit for the dehumidification process.
  • Thermal response and hydrogen gas generation are examined in the Fuel Transfer System (FTS) for fuel transfer.
  • The transient and severe accident analysis capability of the SAS4A/SASSYS-1 code developed by Argonne National Laboratory is coupled with the radionuclide transport analysis capability of the FATE code to predict radionuclide release from a broad spectrum of accidents that can be postulated to occur at liquid metal cooled reactor facilities.
  • Hydrogen risk during the steam generator wet layup additive process was analyzed. The secondary side of the steam generator and piping leading up to the automatic relief valves were modeled using FATE.
  • Hydrogen accumulation in the AP1000 auxiliary building and primary containment building was analyzed in the event of a break in the chemical and volume control system (CVS) hydrogen injection line.

Download Our Process Safety Management (PSM) Overview