Concurrent Upward Flame Spread over a Fire Resistant Fabric (Nomex) under External Heating

Date

2017-07-16

Journal Title

Journal ISSN

Volume Title

Publisher

47th International Conference on Environmental Systems

Abstract

Fire resistant materials are used in multiple applications (clothing, curtains, tents, etc.) were protection from a potential fire is needed. Particularly relevant for this work is the application for astronaut space suits since a spacecraft environment may be different than atmospheric ones. Furthermore, their fire resistant capacity are often tested under very specific conditions that might not represent the real fire situations. For example, when a material is exposed to a near fire or different environmental conditions like reduced pressure, enriched oxygen concentration and micro-gravity, its flammability and fire behaviors can be altered. In this work, an experimental study was performed to investigate the effect of ambient pressure and oxygen concentration on the upward flame spread over a typical fire resistant fabric (Nomex HT90-40) exposed to two different external heat sources. One is the radiation from infrared lamps and the other is the flame from a burning polymethyl methacrylate (PMMA) sheet placed below the fabric. The limiting oxygen concentration (LOC) was first quantified under different external heating, and then the upward flame-spread rate above LOC was measured. Experiments show that the flame from nearby burning object not only can ignite the fire resistant fabric, but also extend the LOC of the material to lower oxygen concentrations. Moreover, the heating from the attached flame is different from an external radiant flux. The results of this work also provide important information about the fire interactions of different materials, and guide the future fire safety design in space exploration.

Description

Maria Thomsen, University of California Berkeley, USA
Xinyan Huang, University of California Berkeley, USA
Alain Alonso, GIDAI, University of Cantabria, Spain
Carlos Fernandez-Pello, University of California Berkeley, USA
David Urban, NASA Glenn Research Center, USA
Gary Ruff, NASA Glenn Research Center, USA
ICES509: Fire Safety in Spacecraft and Enclosed Habitats
The 47th International Conference on Environmental Systems was held in South Carolina, USA on 16 July 2017 through 20 July 2017.

Keywords

Fire resistant, flame spread, Nomex, PMMA, LOC

Citation