Skip to Main Content
Ignition delay of combustible materials in normoxic equivalent environmentsAuthor(s): Sara McAllister; Carlos Fernandez-Pello; Gary Ruff; David Urban
Source: In: SAE 39th International conference on environmental systems; July 12-15 2009; Savannah, GA: paper 2009-01-2491.
Publication Series: Miscellaneous Publication
PDF: View PDF (477.92 KB)
DescriptionMaterial flammability is an important factor in determining the pressure and composition (fraction of oxygen and nitrogen) of the atmosphere in the habitable volume of exploration vehicles and habitats. The method chosen in this work to quantify the flammability of a material is by its ease of ignition. The ignition delay time was defined as the time it takes a combustible material to ignite after it has been exposed to an external heat flux. Previous work in the Forced Ignition and Spread Test (FIST) apparatus has shown that the ignition delay in the currently proposed space exploration atmosphere (approximately 58.6 kPa and 32% oxygen concentration) is reduced by 27% compared to the standard atmosphere used in the Space Shuttle and Space Station. In order to determine whether there is a safer environment in terms of material flammability, a series of piloted ignition delay tests using polymethylmethacrylate (PMMA) was conducted in the FIST apparatus to extend the work over a range of possible exploration atmospheres. The exploration atmospheres considered were the normoxic equivalents, i.e. reduced pressure conditions with a constant partial pressure of oxygen. The ignition delay time was seen to decrease as the pressure was reduced along the normoxic curve. The minimum ignition delay observed in the normoxic equivalent environments was nearly 30% lower than in standard atmospheric conditions. The ignition delay in the proposed exploration atmosphere is only slightly larger than this minimum. In terms of material flammability, normoxic environments with a higher pressure relative to the proposed pressure would be desired.
- You may send email to email@example.com to request a hard copy of this publication.
- (Please specify exactly which publication you are requesting and your mailing address.)
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
CitationMcAllister, Sara; Fernandez-Pello, Carlos; Ruff, Gary; Urban, David. 2009. Ignition delay of combustible materials in normoxic equivalent environments. In: SAE 39th International conference on environmental systems; July 12-15 2009; Savannah, GA: paper 2009-01-2491.
Keywordsflammability, ignition delay, Forced Ignition and Spread Test (FIST)
- The combined effect of pressure and oxygen concentration on piloted ignition of a solid combustible
- Ignitability analysis using the cone calorimeter and lift apparatus
- Critical mass flux for flaming ignition of wood as a function of external radiant heat flux and moisture content
XML: View XML