Extinguishment of Cup-Burner Flames in Low Gravity

Published

January 1, 2005

Author(s)

F Takahashi, Gregory T. Linteris, V Katta

Abstract

The effects of oxidizer stream velocity and oxygen concentration, as well as gravity and pressure, on the extinguishment limits of laminar co-flow diffusion flames of methane, formed in a cup-burner apparatus, have been studied experimentally and computationally. A first attempt was made to measure the cup-burner minimum extinguishing concentration (MEC) of CO2 in microgravity ( g) aboard the NASA Reduced Gravity Aircraft (KC-135). Numerical simulations with detailed chemistry and radiative heat-loss models were performed to reveal the flame structure during the unsteady blowoff-type extinguishing processes and to predict the extinguishment limits. The MEC values determined for various oxidizing environments were:Experiment Computation Air/1g/1 atm (15.7 0.6) % 14.5 % (16.1 %) Air/1g/0.7 atm (15.4 0.5) % 13.5 % 30 % O2/1g/1 atm (34.0 1.2) % 31.0 % 30 % O2/1g/0.7 atm (32.4 1.1) % 29.9 % 21 % O2/ g/1 atm (21.4 0.7) % 19.1 % Considering the complex chemistry and flow-field interactions in the blowoff extinguishment processes, the predicted MEC values were consistently in good agreements (8 % less on average) with the measurements. The relatively high MECs of CO2 in oxygen-enriched environments point to a need for further trade-off studies of fire-extinguishing agents suitable for spacecraft and surface habitats in space exploration.

Proceedings Title

43rd

Conference Dates

January 10-13, 2005

Conference Location

Undefined

Conference Title

AIAA Aerospace Science Meeting and Exhibit

Pub Type

Conferences

Download Paper

Local Download

Keywords

cup burner, fire suppression, flame extinction, flame extinguishment, halon replacements, microgravity combustion

Citation

Takahashi, F. , Linteris, G. and Katta, V. (2005), Extinguishment of Cup-Burner Flames in Low Gravity, 43rd, Undefined, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=861350 (Accessed April 26, 2024)