TB 26-04 Updates and Modernization of NASA’s Chemical Equilibrium with Applications (CEA) Code
For more information, contact Mark K. Leader, Glenn Research Center, mark.leader@nasa.gov Download the PDF version NASA’s Chemical Equilibrium with Applications (CEA) code is a foundational tool for propulsion system analysis. It provides equilibrium chemistry, rocket performance
Search
Suggested Searches
- Climate Change
- Artemis
- Expedition 64
- Mars perseverance
- SpaceX Crew-2
- International Space Station
- View All Topics A-Z
- Home
- Missions
- Humans in Space
- Earth
- The Solar System
- The Universe
- Science
- Aeronautics
- Technology
- Learning Resources
- About NASA
- Español
Featured
  
Back
- Search All NASA Missions
- A to Z List of Missions
- Upcoming Launches and Landings
- Spaceships and Rockets
- Communicating with Missions
- Artemis
- James Webb Space Telescope
- Hubble Space Telescope
- International Space Station
- OSIRIS-Rex
- Explore Earth Science
- Climate Change
- Earth, Our Planet
- Earth Science in Action
- Earth Multimedia
- Earth Data
- Earth Science Researchers
- The Sun
- Mercury
- Venus
- Earth
- The Moon
- Mars
- Jupiter
- Saturn
- Uranus
- Neptune
- Pluto & Dwarf Planets
- Asteroids, Comets & Meteors
- The Kuiper Belt
- The Oort Cloud
- Skywatching
- Exoplanets
- The Search for Life in the Universe
- Stars
- Galaxies
- Black Holes
- The Big Bang
- Dark Energy
- Dark Matter
- Earth Science
- Planetary Science
- Astrophysics & Space Science
- The Sun & Heliophysics
- Biological & Physical Sciences
- Lunar Science
- Citizen Science
- Astromaterials
- Aeronautics Research
- Human Space Travel Research
- Science in the Air
- NASA Aircraft
- Flight Research Innovation
- Supersonic Flight
- Air Traffic Solutions
- Green Aviation Tech
- Drones & You
- Technology Transfer & Spinoffs
- Space Travel
- Living in Space
- Lunar Surface Technology
- Manufacturing and Materials
- Robotics
- Science Instruments
- Computing
- For Kids and Students
- For Educators
- For Colleges and Universities
- For Professionals
- Science for Everyone
- Requests for Exhibits, Artifacts, Speakers & Flyovers
- STEM Engagement at NASA
- NASA's Impacts
- Centers and Facilities
- Directorates
- Organizations
- People of NASA
- Careers
- Internships
- Our History
- Doing Business with NASA
- Get Involved
- Contact
- News Releases
- Recently Published
- Video Series on NASA+
- Podcasts & Audio
- Blogs
- Newsletters
- Social Media
- Media Resources
- Events
- Upcoming Launches & Landings
- Virtual Guest Program
- NASA+
- Images
- NASA Live
- NASA Apps
- Podcasts
- Image of the Day
- e-Books
- 3D Resources
- Interactives
- STEM Multimedia
- NASA Brand & Usage Guidelines
Featured
  
Highlights
  
Highlights
  
Highlights
  
Featured
  
Highlights
  
Highlights
  
Highlights
  
Featured
Featured
  
Highlights
  
4 min read
# TB 26-04 Updates and Modernization of NASA’s Chemical Equilibrium with Applications (CEA) Code
!The headshot image of Daniel Hoffpauir
Daniel Hoffpauir
Aug 21, 2026
Article
Contents
- Background
- Technical Improvements
- Modern Software Architecture
- Expanded Species and Thermodynamic Data
- New Modeling Capabilities
- Performance Improvements
- Guidance for Engineering Use
- References
_For more information, contact Mark K. Leader, Glenn Research Center, mark.leader@nasa.gov_
NASA’s Chemical Equilibrium with Applications (CEA) code is a foundational tool for propulsion system analysis. It provides equilibrium chemistry, rocket performance, shock, and detonation calculations used across NASA and the broader aerospace community. NASA Engineering and Safety Center (NESC) Activity TI-22-01730 modernized the legacy CEA2 Fortran code into CEA v3, a Fortran 2008, object-oriented software package with expanded interface support, updated thermochemical data, improved maintainability, and substantially improved workflow integration. The modernized code preserves backward compatibility with legacy CEA input workflows while enabling direct use from modern analysis environments, including Python, C, MATLAB, and automated design studies.
Background
CEA2 was released in 2002 and has remained widely used for propulsion and thermochemistry analysis. However, the original procedural Fortran implementation became increasingly difficult to maintain, extend, and integrate into modern engineering workflows due to the lack of a subroutine interface. Current propulsion analysis increasingly requires automated parametric sweeps, integration with other modeling tools and engineering workflows, and support for emerging propellants and fuels, including green propellants and sustainable aviation fuels. These needs motivated a comprehensive modernization effort to preserve CEA’s validated technical basis while improving its maintainability, usability, and integration with modern engineering software.
Technical Improvements
Modern Software Architecture
CEA v3 is implemented in Fortran 2008 using object-oriented data structures, stricter typing, and a thread-safe equilibrium solver architecture. The software supports Fortran, C, Python, MATLAB, and Excel interfaces. These interfaces allow CEA to be used directly in automated analysis pipelines, multidisciplinary design frameworks, and high-volume designof- experiments studies. Backward compatibility is supported through a legacy command-line interface, allowing existing CEA input files and workflows to be carried forward with minimal disruption.
Expanded Species and Thermodynamic Data
The thermodynamic database has been expanded to support additional propellants and fuels relevant to current NASA applications, including green propellant constituents such as ADN, HAN, and LMP-103S, and sustainable aviation fuel candidates such as n-Butanol. This expanded species coverage improves the applicability of CEA for next-generation propulsion, green propellant, and sustainable aviation fuel studies.
New Modeling Capabilities
CEA v3 adds or improves support for several modeling capabilities,
including:
- Subroutine interface enabling direct integration and high-volume calculations
- Negative reactant amounts
- Inert hydrocarbon fuel representations, including RP-1, Jet-A, and JP-series fuels
- Analytic total derivatives for coupling with optimization and sensitivity analysis workflows
Performance Improvements
For standalone use, individual equilibrium calculations in CEA v3 are moderately slower than comparable CEA2 calculations because the modernized architecture and added robustness introduce additional computational overhead. In representative testing, a single calculation was approximately 40 percent slower, but the absolute difference was only about 0.004 seconds per case. However, the modernized architecture provides substantial performance advantages for multi-case workflows, which are common in design-of-experiments studies, parametric sweeps, optimization, and uncertainty analyses. In one benchmark, a sweep of 108,500 cases completed in approximately 1.11 seconds with CEA v3, compared with approximately 15 minutes using CEA2. This corresponds to an approximately 800-times reduction in runtime for that workflow. These improvements make large-scale propulsion trade studies and automated design-space exploration significantly more practical.
Guidance for Engineering Use
NASA engineering users should consider the following guidance:
- Use CEA v3 for new propulsion and thermochemistry analyses when possible to take advantage of the modernized interfaces, expanded database, and improved workflow integration.
- Use the Python, MATLAB, or C interfaces for automated workflows, including parametric sweeps, optimization studies, and iterative design analyses.
- Use the updated species database for green propellant and sustainable aviation fuel studies when the relevant species are included and validated for the intended application.
- Use the classic command-line interface when continuity with legacy CEA workflows or input files is required.
- Retain appropriate engineering review and validation when transitioning established CEA2 workflows to CEA v3, particularly for mission-critical analyses or cases that depend on legacy assumptions.
References
1. NASA/TM–20260007987
2. CEA documentation: https://nasa.github.io/cea
3. CEA repository: https://github.com/nasa/cea
Was this page helpful?
Δ
Was this page helpful?
Yes
No
×
Notifications