Coarse-grain cross sections for rovibrational excitation and dissociation of the N2-N system

Erik Torres, Richard L. Jaffe, David Schwenke, Thierry E. Magin

Research output: Contribution to journalArticlepeer-review

3 Scopus citations


We present a method to generate analytical coarse-grain cross sections for internal energy excitation and dissociation of nitrogen and apply it to the NASA Ames N2-N ab initio database. State-resolved cross sections from this database are reduced using the Uniform RoVibrational-Collisional bin model. With a 10-bin system as example we compare two sets of coarse-grain cross sections: one obtained by analytical inversion and another by direct binning. With analytical inversion we manage to compress the entire set of state-resolved data into a small set of parameters, sufficient to reconstruct the main features of the full database. This has the potential of massively reducing the computational cost in large-scale direct simulation Monte Carlo (DSMC) calculations, both concerning memory requirements and execution time. Combining this coarse-grain model with the N2-N ab initio database will enable much higher-fidelity DSMC simulation of nonequilibrium dissociation in shock-heated flows than is currently possible with conventional models.

Original languageEnglish (US)
Article number110701
JournalChemical Physics
StatePublished - May 1 2020

Bibliographical note

Funding Information:
Research of T.E. Magin was sponsored by the European Research Council Starting Grant #259354. The authors would like to thank Mr. Federico Bariselli for his contributions to the improvement of the URVC bin model.

Publisher Copyright:
© 2020 Elsevier B.V.


  • Coarse-grain models
  • Direct simulation Monte Carlo (DSMC)
  • Non-equilibrium flows
  • Reaction cross sections


Dive into the research topics of 'Coarse-grain cross sections for rovibrational excitation and dissociation of the N2-N system'. Together they form a unique fingerprint.

Cite this