TB 26-04 Updates and Modernization of NASA’s Chemical Equilibrium with Applications (CEA) Code

NASA’s Chemical Equilibrium with Applications (CEA) code is a critical tool for propulsion system analysis, providing equilibrium chemistry and rocket performance calculations widely used across NASA and the aerospace industry. The 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. The update includes expanded interface support for Python, C, MATLAB, and automated design studies, along with updated thermochemical data and improved maintainability, while ensuring backward compatibility with existing CEA input workflows.

The modernization effort addressed challenges with the original procedural Fortran implementation, which had become difficult to maintain and integrate into modern engineering workflows. CEA v3 introduces a thread-safe equilibrium solver architecture and stricter typing, enabling direct use in automated parametric sweeps, multidisciplinary design frameworks, and high-volume design-of-experiments studies. The expanded thermodynamic database now supports additional propellants and fuels, including green propellants such as ADN, HAN, and LMP-103S, as well as sustainable aviation fuel candidates like n-Butanol, enhancing its relevance for next-generation propulsion research.

Performance testing revealed that individual equilibrium calculations in CEA v3 are approximately 40 percent slower than CEA2 due to added robustness and modern architecture overhead, though the absolute difference per case is minimal at about 0.004 seconds. However, CEA v3 demonstrates substantial performance gains for multi-case workflows, completing a sweep of 108,500 cases in approximately 1.11 seconds compared to 15 minutes with CEA2, representing an 800-times reduction in runtime for such workflows.

The updated CEA v3 code is now available through NASA’s GitHub repository and documented for public use. For further details, inquiries can be directed to Mark K. Leader at NASA’s Glenn Research Center. The modernization ensures CEA remains a practical and efficient tool for propulsion analysis amid evolving aerospace requirements and emerging fuel technologies.