Fire Safety in Space – Beyond Flammability Testing of Small Samples

Grunde Jomaas (1) , Jose L Torero (2) , Christian Eigenbrod (3) , Justin Niehaus (4) , Sandra Olson (4) , Paul Ferkul (5) , Guillaume Legros (6) , Carlos Fernandez-Pello (7) , Adam Cowlard (8) , Sébastien Rouvreau (9) , Nickolay Smirnov (10) , Osamu Fujita (11) , James t'Ien (12) , Gary Ruff (4) , David Urban (4)

1 DTU - Danmarks Tekniske Universitet = Technical University of Denmark
2 UQ [All campuses : Brisbane, Dutton Park Gatton, Herston, St Lucia and other locations] - The University of Queensland
3 ZARM - Center of Applied Space Technology and Microgravity
4 NASA Glenn Research Center
5 USRA - Universities Space Research Association [Washington]
6 IJLRDA-FRT - Fluides Réactifs et Turbulence
7 LBNL - Lawrence Berkeley National Laboratory [Berkeley]
8 School of Engineering [Edinburgh]
9 Belisama R&D
10 MSU - Université d'État Lomonossov de Moscou = Lomonosov Moscow State University
11 Hokkaido University [Sapporo, Japan]
12 Case Western Reserve University [Cleveland]

An international research team has been assembled to reduce the uncertainty and risk in the design of spacecraft fire safety systems by testing material samples in a series of flight experiments (Saffire 1, 2, and-3) to be conducted in an Orbital Science Corporation Cygnus vehicle after it has undocked from the International Space Station (ISS). The tests will be fully automated with the data downlinked at the conclusion of the test before the Cygnus vehicle re-enters the atmosphere. The unmanned, pressurized environment in the Saffire experiments allows for the largest sample sizes ever to be tested for material flammability in microgravity, which will be based on the characteristics of flame spread over the surface of the combustible material. Furthermore, the experiments will have a duration that is unmatched in scale compared to earth based microgravity research facilities such as drop towers (about 5 seconds) and parabolic flights (about 20 seconds). In contrast to sounding rockets, the experiments offer a much larger volume, and the reduction in the oxygen concentration during the Saffire experiments will be minimal. The selection of the experimental settings for the first three Saffire experiments has been based on existing knowledge of scenarios that are relevant, yet challenging, for a spacecraft environment. Given that there is always airflow in the space station, all the experiments are conducted with flame spread in either concurrent or opposed flow, though with the flow being stopped in some tests, to simulate the alarm mode environment in the ISS and thereby also to study extinguishment. The materials have been selected based on their known performance in NASA STD-6001Test-1, and with different materials being classified as charring, thermally thin, and thermally thick. Furthermore, materials with non-uniform surfaces will be investigated.

Mots clés: Flame propagation; microgravity; fire safety; experiments; flammability

Domaines: Milieux fluides et réactifs

Grunde Jomaas, Jose L Torero, Christian Eigenbrod, Justin Niehaus, Sandra Olson, et al.. Fire Safety in Space – Beyond Flammability Testing of Small Samples. Acta Astronautica, 2015, 109, pp.208 - 216. ⟨10.1016/j.actaastro.2014.11.025⟩. ⟨hal-01524495⟩