Nuclear Science, Technology, and Engineering for Molten Salt Reactors

Modeling and Simulation

The “Modeling and Simulation” research thrust can be divided into three sections:

  • High Fidelity Modeling;
  • Reduced-Order Models (ROM); and
  • System Analysis.
Reduced-order model for flow hydrodynamics in fast
spectrum MSR

High-Fidelity and Reduced-Order Simulations

Molten salt reactors have unique features related to fuel form and motion that current (e.g., LWRs) code systems cannot model:

  • Delayed neutron precursor drift
  • Salt (fuel/salt) compressibility
  • Radiative heat transfer
  • Salt freezing
MSRE mesh for precursor drift study

Goal / Need

Understanding such phenomena is necessary for a proper design and safety assessment of MSRs

Our Approach

  • High-fidelity modeling tools based on first principles (due to lack of MSR experimental data)
    • Can be very greedy in CPU time + memory
  • Model-order reduction to significantly speed up simulations
    • Requires data produced from high-fidelity simulations to train reduced models
    • Enables faster design & scoping studies and Uncertainty Quantification

Highlights

Multiphysics modeling of delayed neutron precursor drift effect: 2000-6000x speed-ups with reduced order models.

Neutronic study on precursors drift

Joint Collaboration on Models

  • MSRE (UC-Berkeley)
  • MSFR (Texas A&M)

Researchers

High-Fidelity Models:

Reduced-Order Models:

Engagements

Oak Ridge National Laboratory

System Performance and Analysis

Motivation

  • Need for thermo-physical properties compilation, synthesis and dissemination
  • Need for MSR design and deployment analysis and system optimization focusing on operations/resources metrics
  • Need for MSR system-level dynamics and control
  • Need for  licensing and 3SBD (safety, security and safeguards by design) evaluations for MSRs

Team Integration

  • Data exchange – salt properties
  • Common tools – Serpent, MATLAB, python
  • Models – thermal and fast configurations

Goal

Integrated design development and system optimization in support of MSR deployment

Efforts

System analysis & optimization framework, UQ Analysis accounting for salt properties, system design evaluations

  • Configurations and long-term U-TRU evolution and MSR metrics
  • Waste management (minimization) and sustainability in fuel cycles with MSRs
  • Salt recipe design algorithm accounting for solubility/phase transitions/liquidus temperature vs. reactor performance characteristics and MSR operational dynamics and stability

Accomplishments

  • Compiled salt property database
  • Developed an approach to synthesize salt composition thermo-physical properties
  • Assembled a set of reference MSR configurations
  • Developed metrics for MSR analytics
  • Completed preliminary sensitivity evaluations

Researchers

Faculty:

Students:

External Collaborators

  • OECD-NEA
  • GIF MSR
  • DOE NE, NE-KAMS
  • IAEA databases.
  • 2nd ed. Gen. IV Systems Handbook team