PROBE - A Digital Computer Program for Computing Langmuir Probe Current-Voltage Characteristics.
Abstract
This report documents PROBE - A digital computer program for computing Langmuir probe current-voltage characteristics. PROBE computes current-voltage characteristics and potential, electric field, and charged particle density profiles for a spherical Langmuir probe in a collision dominated slightly ionized gas. The operating point for a Langmuir probe is probe radius, plasma charged particle density, plasma charged particle temperatures and collision frequencies between the charged particles and neutral particles. The computation is performed by numerically integrating a set of plasma transport differential equations which conserve mass momentum and energy in one dimensional spherical geometry. Computed characteristics have been obtained for a broad range of plasma conditions including collisionless and collision dominated extremes. The computed probe characteristics have been compared with previous results and the theoretical approach is concluded to be sound. Current-voltage characteristics computed with PROBE have the correct theoretical dependence in the collisional limit (yielding the Maxwell or temperature line for highly retarding potentials and exhibiting diffusion limited saturation for highly accelerating potentials) and in the collisionless limit yielding the Maxwell or temperature line for retarding potentials and the collisionless thick sheath limit for accelerating potentials). (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1972
- Accession Number
- AD0903665
Entities
People
- D. J. Rush
- R. J. Mccandless
Organizations
- General Electric