H.E.A.T. Documentation
Contents
General Information
The Heat flux Engineering Analysis Toolkit (HEAT) is a suite of tools for predicting the heat flux incident upon PFCs in tokamaks, and the associated PFC state (e.g. temperature). The toolkit connects CAD, FVM, FEM, MHD, ray tracing, plasma physics, and more, in one streamlined package. The objective is to enable engineers and physicists to quickly ascertain heat loads given specific magnetic and geometric configurations. HEAT has been used to design the SPARC PFCs and continues to be developed for control room use as SPARC begins operations.
- Some examples of what HEAT can predict:
3D heat loads from 2D and 3D plasmas for limited and diverted discharges
Heat fluxes from the optical approximation, ion gyro orbit approximation, and photon flux
Heat and particle fluxes from filaments and runaway electrons
3D heat flux profiles from RMPs and Error Fields
Time varying heat loads and temperature profiles
Magnetic field line traces
Many other quantities
- The latest release of HEAT is v4.2, which includes notable additions such as:
Mitsuba3 for photon tracing
Ability to read STLs directly instead of STEPs (Bring Your Own Mesh)
A Runaway Electron module (A. Feyrer, MIT)
Ability to read arbitrary R,Z,qPar profiles from CSV (E. Tinacba, ORNL)
Full installation instructions and tutorials (including Docker) are in the Install and Docker sections below and on Read the Docs: https://heat-flux-engineering-analysis-toolkit-heat.readthedocs.io/en/latest/
Citing HEAT
To cite HEAT, use the open-access paper in Fusion Science and Technology: https://doi.org/10.1080/15361055.2021.1951532
- Other HEAT-related publications (recent first):
The Experimental Validation of HEAT on the ASDEX Upgrade Tokamak, A. Redl et al. 2025
3D modeling of n = 1 RMP driven heat fluxes on the SPARC tokamak PFCs using HEAT, M. D’Abusco et al. 2025
Development and validation of non-axisymmetric heat flux simulations with 3D fields using the HEAT code, A. Wingen et al. 2025
Shadow masks predictions in SPARC tokamak plasma-facing components using HEAT code and machine learning methods, D. Corona et al. 2025
HEAT simulation and IR data comparison for ST40 plasma-facing components, E. Tinacba et al. 2024
SPARC power exhaust workflows using open source tools (APS DPP Tutorial), presentation
3D ion gyro-orbit heat load predictions for NSTX-U, Looby et al., https://iopscience.iop.org/article/10.1088/1741-4326/ac8a05
3D PFC Power Exhaust Predictions for the SPARC Tokamak, Looby et al., https://meetings.aps.org/Meeting/DPP22/Session/NO03.11
Measurements of multiple heat flux components at the divertor target by using surface eroding thermocouples (invited), Ren et al., https://aip.scitation.org/doi/full/10.1063/5.0101719
SHEFT (HEAT predecessor), A. Wingen 2019, https://info.fusion.ciemat.es/OCS/EPS2019PAP/pdf/P2.1040.pdf
The MAFOT code (A. Wingen) is documented at https://github.com/ORNL-Fusion/MAFOT/tree/master/doc
Running HEAT
To run HEAT, download the HEAT Docker container from Docker Hub (tested on Linux, macOS, and Windows). See the Install and Docker pages for details.
Docker Hub: https://hub.docker.com/r/plasmapotential/heat
HEATtools (pre/post processing): https://github.com/plasmapotential/HEATtools
This repository uses Git LFS for large data files (e.g. the 3D fields test case). After cloning, run:
git lfs install
git lfs pull
before running the 3D fields test case (e.g. ./runTerminalModeTest3Dfields).
Developer and license
The developer is Tom Looby, Scientist at Commonwealth Fusion Systems. Contact: tlooby@cfs.energy
This project is open source under the MIT license. Contributions are welcome (documentation, code, issues); see the GitHub repository for more.
Visualization (ParaVIEW)
To visualize HEAT results you need ParaView. HEAT can produce time-varying 3D heat fluxes and visualizations that work with ParaView.
ParaView: https://www.paraview.org/
Download: https://www.paraview.org/download/
Note: Work has been done to integrate ParaviewWeb into the HEAT HTML interface; this is not included in the current releases.