Computational Physics and Chemistry
Rarified Gas Dynamic Flow Fields
Spectral Sciences' work in modeling rocket plumes and the atmospheric environment around spacecraft includes calculations of molecular flow and radiation fields using first-principles Monte Carlo techniques. Examples of SSI-developed flow field modeling codes include:
- SOCRATES (Spacecraft/Orbiter Contamination Representation Accounting for Transiently Emitted Species) is a Direct Simulation Monte Carlo (DSMC) code designed to predict the contamination and radiation environment around spacecraft. It is designed for use both as a research tool for specialists (it can simulate arbitrary species, arbitrary chemical reactions, trace species, etc.) and as a user-friendly tool for the non-specialist (it can run and produce useful results with very minimal input).
- NOMAD (Nonequilibrium Original Monte Carlo with Approximate Dynamics) is a free molecular model which describes the dynamical, chemical, and emissive interaction of a plume with a high altitude atmosphere. It melds smoothly with the predictions of SOCRATES at high altitudes, but runs up to three orders of magnitude faster.
-
calculations of O(1S) and O(1D) emission maps in a space shuttle thruster plume