Accession Number : ADA193694

Title :   Progress on a Monte Carlo Shuttle Contamination Model.

Descriptive Note : Rept. for Oct 86-Sep 87,

Corporate Author : SPECTRAL SCIENCES INC BURLINGTON MA

Personal Author(s) : Elgin, James B

PDF Url : ADA193694

Report Date : 01 Feb 1988

Pagination or Media Count : 34

Abstract : This is the second yearly scientific report on a three year effort to develop a Monte Carlo model of contamination for the space shuttle orbiter. Contamination of instruments on the space shuttle orbiter is an issue of major concern. The shuttle gives off matter through surface outgassing, via various thrusters and from flash evaporators. At altitudes where the atmospheric mean free path is comparable to or less than shuttle dimensions, the deposition back onto shuttle-borne instruments will be largely determined by the multiple collision environment surrounding the shuttle. Even at higher altitudes, this may be the dominant source of contaminants for some portions of the shuttle. In addition to physical contamination of shuttle surfaces, 'radiation contamination' is also a potential problem as gases surrounding the shuttle collide at high speed with atmospheric molecules. These energetic collisions can lead to vibrational excitation and subsequent radiative decay. A similar issue of some concern is the presence of ions in the vicinity of the shuttle which can (possibly) be produced via the critical ionization velocity effect. It has been named the SOCRATES code, which is an acronym for Shuttle Orbiter Contamination Representation Accounting for Transiently Emitted Species.

Descriptors :   *CONTAMINATION, *SPACE SHUTTLES, *FLOW FIELDS, *MONTE CARLO METHOD, FLUX(RATE), STATISTICS, SURFACES, MATHEMATICAL MODELS, COMPUTATIONS, CONTOURS, THREE DIMENSIONAL, SPACE SYSTEMS

Subject Categories : Manned Spacecraft

Distribution Statement : APPROVED FOR PUBLIC RELEASE