Effect Of Oxygen Concentration On The Carbon Monoxide Yields From Methane And Methanol Flames

Abstract

Reduced oxygen concentration environment by diluting with nitrogen (N 2 ) is expected as one of the alternative fire prevention and extinguishing technologies. To ensure the fire safety under reduced oxygen concentration, it is necessary to explore the carbon monoxide (CO) production because CO is known as a major cause of fatalities in compartment fire. To reveal the CO production in gaseous and liquid combustion under reduced oxygen concentration, the CO yield under oxygen-reduced condition was investigated experimentally using a cup burner. CH 4 and CH 3 OH were used as fuels and supplied through the inner cup. Mixtures consisting of oxidizer (O 2 ) and fire extinguishing agent (N 2 ) were issued through the outer chimney. The relative percentages of O 2 /N 2 were varied, maintaining the total flow rate of O 2 + N 2 constant. The CO concentration in the post-combustion mixture was measured as a function of the oxygen concentration. In the case of CH 4 flame, the CO concentration was increased with decreasing O 2 concentration. In contrast, in the case of CH 3 OH, the CO concentration was decreased with decreasing O 2 concentration. The results show that the influence of the oxygen concentration on the CO production yield in liquid combustion is apparently different from that of gaseous combustion.

Experimental study on fire hazard of typical curtain materials in ISO 9705 fire test room

“…HRR is an important parameter in describing fire hazard. This study has accordant HRR values with the previous work of the authors 19. Figure 8 presents the time‐dependent HRR curves from ignition to 300 s afterwards for experiments in this paper.…”

“…The correlation between flame spread rate and HRR is discussed. As CO is known as a major cause of fatalities in compartment fires 19, the emitted CO and CO 2 from curtain fire was also researched in this paper. The purpose is to make the description of curtain fire behavior proper and the results would be helpful in building fire simulation and fire safety design.…”