Application of the Saha Equation to High Temperature (> or = 6000K) rocket Exhaust
Abstract
Using the SAHA equations and spectroscopic constants, the computer program in this report calculates the species populations of diatomic molecules, neutrals, ions, and electrons in a plasma. The code considers the equilibrium of a two-elements, chemically reacting plasma, by calculating the partition function for each species. By rederiving theoretically, as the JANNAF tables do, the thermodynamic properties of a rocket propellant, but using extended excitation levels, the program can estimate (above 6000 K) performance of advanced propulsion concepts. This second edition code described here considers in addition to mixtures of carbon (C), hydrogen (H), nitrogen (N), and oxygen (0), the species of argon (Ar), up through Cv, HII, NIV, OV, and ArV; any diatomic combination of these elements, both neutral and singly ionized. The user can enter in spectroscopic data for his own elements. Program results agree with JANNAF tables at 6000 K, for dominant species; output graphs of nitrogen species densities (3000 K to 30,000 K) and air species mole fractions (3000 K to 10,000 K) match published data. The second edition also has the additional feature of being able to calculate rocket performance based upon the input of a specific quantity of energy when running the code. This is especially valuable for calculating the high temperature performance of laser, fusion, and antiproton thermal propulsion systems which add heat to a working fluid or propellant.... SARA Equations, Interplanetary missions, Spectroscopy constants thermodynamic properties of rocket propellants, Fortran code.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1993
- Accession Number
- ADA264004
Entities
People
- Robert T. Nachtrieb