Accession Number:

ADA285234

Title:

ARCJET Plasma Modeling with Experimental Validation

Descriptive Note:

Annual technical rept. 30 Jul 1993-1 Sep 1994

Corporate Author:

ILLINOIS UNIV AT URBANA DEPT OF MECHANICAL AND INDUSTRIAL ENGINEERING

Report Date:

1994-09-01

Pagination or Media Count:

82.0

Abstract:

We report for the first time thermal non-equilibrium separate electron and gas temperatures numerical results for a hydrazine arcjet. All viscous flow properties are considered, assuming laminar axisymmetric flow. The model includes anode temperature distribution, and the electrical conductivity is coupled to the flow properties, allowing for a self-consistent current distribution. The numerical solution algorithm employs the compressible form of the PISO algorithm to solve the continuity and momentum equations. Run time is a few hours on a Convex C240 Mainframe with a 44 x 24 grid. Numerical results are presented for low power hydrogen and hydrazine thrusters. Preliminary results of quadruple electrostatic probe measurements at the exit plane of a 1 kW hydrazine arcjet, including ne and Te profiles, are presented. The quadruple probe model includes the effects of Te and ne gradients across the probe volume to extract Te and ne radial profiles from the asymmetric raw probe data. A time-of-flight electrostatic probe technique for measuring heavy particle velocities is described which, when coupled with the quadruple probe data can yield radial profiles of ner, Ter, Tir and uir. Experimental investigations of the energy deposition processes in the nozzle and constrictor regions of a 1-2 kill hydrazine arcjet are being performed. Electron number density and electron temperature measurements, using an array of flush-mounted Langmuir probes, will be made in the boundary layer, while emission spectroscopy will prolvide property measurements in the core flow.

Subject Categories:

  • Fluid Mechanics
  • Thermodynamics
  • Electric and Ion Propulsion

Distribution Statement:

APPROVED FOR PUBLIC RELEASE