An experimental study of _{N 2} dilution effects on _{CH 4} – _{O 2} flame stabilization characteristics in a two-section porous medium

다국어 초록 (Multilingual Abstract)

<P><B>Abstract</B></P> <P> <SUB> N 2 </SUB> dilution effects on <SUB> CH 4 </SUB> – <SUB> O 2 </SUB> flame stabilization in a two-section porous medium burner were experimentally investigated for its potential application to the destruction of highly <SUB> N 2 </SUB> -diluted <SUB> CF 4 </SUB> . The burner was made up of two axially-stacked silicon carbide foams having different pore sizes. Various flame behaviors, such as stable flame, flashback, blowout, extinction and transient flames, were observed and, for the stable flame, temperature distributions and exhaust gas emissions were measured. Results showed that the flame was only stable in a belt-like region on the domain of fuel flow rate and oxygen concentration. The region boundaries, termed as <SUB> O 2 </SUB> -enriched and <SUB> O 2 </SUB> -deficient limits, were determined for various equivalence ratios. It was found that our burner configuration was able to sustain the submerged combustion even under the <SUB> N 2 </SUB> dilution amounting to at least 10.4 times of <SUB> CH 4 </SUB> flow rate. In addition, temperature measurements showed that the stable flames could have their peak temperatures higher than 1600 ° C , which is known to be a thermal destruction temperature of <SUB> CF 4 </SUB> . These results may indicate that porous media burners can practically applied in destructing highly <SUB> N 2 </SUB> -diluted <SUB> CF 4 </SUB> with a reduced fuel consumption.</P> <P><B>Highlights</B></P> <P> <UL> <LI> N<SUB>2</SUB> dilution effects on various flame behaviors in a two-section porous medium. </LI> <LI> O<SUB>2</SUB>-enriched and O<SUB>2</SUB>-deficient limits of stable flames. </LI> <LI> High temperature combustion to destruct highly-diluted nondegradable gases. </LI> <LI> Estimated fuel consumption being less than those of commercial devices. </LI> </UL> </P>