ARISTOTLE – Low Pressure Flow Model

ARISTOTLE (A Rarefied, Industrial gas Simulation Tool On The cLoud Environment) is a cloud-based, rarefied gas simulation software currently under development at SSI via funding provided by the Department of Energy through the Small Business Innovation Research (SBIR) Program. It is built upon the SPARTA library and the direct simulation Monte Carlo (DSMC) method, which has been successfully applied to rarefied, or low pressure, gas problems for over six decades.


Currently ARISTOTLE is undergoing alpha testing within SSI. To request access to the beta version of ARISTOTLE, which will allow users to predict unsteady, rarefied gas flows around arbitrarily complex surfaces, please fill out this form and a member of SSI’s technical staff will get in contact with you.

DSMC prediction of gas molecules moving through a vacuum chamber. The chamber walls have a sticking coefficient of 1.

technical Contact

Dr. Timothy Deschenes



  • Development of the ARISTOTLE webware

    Rarefied gas dynamics are important for a wide variety of applications. An improvement in the ability of general users to predict these gas flows will enable optimization of current, and discovery of future processes. Despite this potential, most rarefied simulation software is designed by and for experts in the community. This has resulted in low adoption of the methods outside of the immediate RGD community.

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