Accession Number:

ADA413197

Title:

Data Analysis for CHAWS Modeling

Descriptive Note:

Final rept. 30 Sep 1993-31 Mar 2000

Corporate Author:

MASSACHUSETTS INST OF TECH CAMBRIDGE DEPT OF AERONAUTICS AND ASTRONAUTICS

Personal Author(s):

Report Date:

2000-03-24

Pagination or Media Count:

27.0

Abstract:

We report here on results on two related areas of plasma-structure interaction the analysis of data on ion collection by a negative probe in the wake of large objects CHAWS experiment, and the modeling of electron collection by a bare positive tether in a low Earth orbit. In the first area, our analysis contributed to a number of important conclusions, including the identification of a probable density probe miscalibration, quantification of the role of H ion collection particularly at low bias, and description of the cylindrical-to-spherical probe sheath transition as bias increases. In the tether modeling ara, we have been able to move beyond the classical analysis of Laframboise for a non-moving, non-magnetized cylindrical probe by including both a meso-thermal plasma flow, and a cross-magnetic field, both representative of orbital conditions. The full Particle-in-Cell codes we developed predict that, in the presence of the cross-flow, current collection exceeds the Orbital Motion Limit by a factor close to 2. Preliminary analysis of these results indicate that the strong plasma fluctuations revealed by the simulation in the frontal ion stagnation area are responsible for the current excess.

Subject Categories:

  • Astronautics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE