Multiphysics · CFD & heat transfer · Materials
FissionFusionGeneral nuclearScientific computing

MOOSE.

Multiphysics Object-Oriented Simulation Environment

MOOSE is an open-source C++ framework from Idaho National Laboratory for building parallel finite-element and finite-volume simulations in which several physics are solved as one fully coupled implicit system on PETSc and libMesh. Engineers write small pluggable objects or assemble ready-made physics modules, link models across scales with MultiApps and Transfers, and run the same input from a laptop to tens of thousands of cores.

Hub betaUpstream exampleSources checked 2026-10-10
Engineering questions it helps answer
  • How do heat conduction, stresses and fluid flow in a component interact when solved as a single coupled implicit system?
  • What is the tritium inventory and permeation through a blanket or first-wall material under coupled heat and mass transport (through MOOSE-based applications)?
  • How does a reactor core or test article respond when neutronics, thermal-hydraulics and fuel performance are coupled across scales?
Physics scope
  • Coupled nonlinear PDE systems solved fully implicitly with Newton–Krylov and automatic differentiation
  • Continuous and discontinuous Galerkin finite elements and finite volumes on adaptive meshes
  • Heat transfer, solid mechanics, contact, Navier–Stokes, porous flow, thermal hydraulics
  • Phase field, chemistry, electromagnetics, ray tracing, level set
  • Optimisation, stochastic tools for uncertainty quantification, surrogates
  • Multiscale coupling through MultiApps and Transfers

Limitations

A framework, not a turnkey analysis tool: most problems need a MOOSE-based application or a carefully built input. Neutronics is deliberately excluded from the open modules and lives in closed-source applications. Releases are date-stamped tags without semantic versions.

Fusion relevance

A general multiphysics framework. Its fusion relevance comes from the applications built on it that the project lists: Cardinal (OpenMC and nekRS coupling), TMAP8 (tritium migration), SALAMANDER (blanket multiphysics), Aurora and Apollo (UKAEA), and others. UKAEA is named as a major contributor in the project's copyright file.

Upstream examples

Published by the project itself. These are the project's own tutorials, not Morton Labs runs.

Reference workflows on this site
Upstream example

Cardinal LWR pincell: OpenMC transport coupled to MOOSE heat conduction

For one pressurised-water-reactor fuel pin, what converged fission heat-source distribution and solid temperature field result when OpenMC eigenvalue transport with temperature feedback is iterated against a MOOSE heat-conduction solve?

Upstream exampleCardinalOpenMCMOOSE
Upstream example

NRIC Virtual Test Bed: tritium in a divertor monoblock during pulsed operation (TMAP8)

How does pulsed tokamak operation change the tritium retained inside an ITER-like tungsten/copper/CuCrZr divertor monoblock and the tritium that permeates through to the coolant tube, when heat conduction and hydrogen-isotope diffusion with trapping are solved together in 2D?

Upstream exampleTMAP8MOOSE
People

Developed by Idaho National Laboratory (operated by Battelle Energy Alliance, LLC), with major contributions credited to CSIRO and the UK Atomic Energy Authority among others. No individual profiles are published for this project yet.

Roles name a specific relationship with evidence. Authorship of a paper is not maintainership, and a listed person is not a Morton Labs partner or endorser.

Source collections

This entry was written by Morton Labs from public sources and last checked on 2026-10-10. Spotted an error, or want something changed or removed? Email zach@mortonlabs.ai with the page address.

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