The Effect of Oxygen Enrichment on Combustion Instabilities for Synthetic Gases Fuels with Different H2/CO Ratios

AbstractNowadays, researches have been concentrating on alternative fuels in the field of energy. Synthetic gasmixtures are gaining importance as one of these alternative fuels. By considering synthetic gas mixturescontaining H2 and CO combustible gases, flame instabilities were investigated in case of burning of syntheticgas mixtures in different H2/CO (3, 1.5, 0.5) ratios with oxygen enrichment. Experiments were carried outunder constant swirl number (1), constant equivalence ratio (0.7) and constant burning power (3 kW). Undernormal conditions, the oxygen rate of 21% by volume in the air was increased to 23% and 25% by supplyingoxygen from an additional tank. The results showed that the oxygen enrichment limit decreases as thehydrogen content in the fuel mixture increases. While the H2 / CO ratio was 0.5 and 1.5, the oxygen enrichmentrate increased to 25%, but it could be increased up to 23% in the mixture with the H2 / CO ratio of 3. Inaddition, the flame stability was interpreted from the dynamic pressure fluctuations caused by external acousticforce at different frequencies by means of the speakers placed in the burner arms. Thus, it was determined thatoxygen enrichment in mixtures with high hydrogen ratio triggers instabilities.Keywords: Synthetic gas, Oxygen Enrichment, Acoustic Enforcement, Instabilities.