Objectives
The objective of this experiment was to enhance the understanding of flame spreading over solid fuel surfaces in low-speed flows by: (1) determining the structure of spreading flames in terms of temperature, species concentrations and velocity fields; and (2) determining the mechanisms that induce flammability limits.
Shuttle-Mir Missions Approach Results
Glovebox environment useful for flame spread tests at the lowest airflow velocities.
Earth Benefits Publications Principal Investigators Co-Investigators
NASA-2
FFFT samples were placed in the FFFT Module in the glovebox facility. The FFFT Module is designed as a low-speed wind tunnel. The samples were ignited in the glovebox; this provided a level of isolation from the Mir environment. Photographs and video recording were taken of the burning samples. Thermocouple temperatures and air velocity were recorded using the glovebox recording system and a color video camera provided by the FFFT experiment. All samples were successfully ignited and burned in very low- speed airflow: Four flat cellulose samples of differing thicknesses, four samples of polyethylene wire insulation.
Video and film images obtained for each sample. Fuel and flame temperatures measured. Comparison of flame structure with numerical simulation of thinnest cellulose sample complete and successful. Wire insulation samples show more complete burning in orbit than in Earth-bound tests.
The engineering of fire prevention, detection, and control depends on understanding how flames spread. The rate of flame spreading is influenced by air motion. The idea behind studying flame spreading in microgravity comes from the unique properties of microgravity, a low air speed environment. Buoyancy effects on the ground creates air streams that can control the rate of flame spreading, which is not present in microgravity. Flame spreading in low-speed air flow helps scientists to test regimes where other mechanisms, such as radiation heat transfer, control spread rates and flammability. Understanding flame spreading in the low-speed air flow environment has application in fire treatment on space vehicles and in structures where air movement is low.
Ferkul, P.V., et al. "Combustion Experiments on the Mir Space Station," AIAA 37th Aerospace Sciences Meeting, AIAA-99-0439, January 1999.
Dr. Kurt Sacksteder
NASA/Lewis Research Center
Prof. James S. T'ien
Mr. Paul S. Greenberg
Dr. Paul V. Ferkul
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Curator:
Julie Oliveaux
Responsible NASA Official: John Uri |
Page last updated: 07/16/1999
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