On the Response of Ultralean Combustion of CH₄/H₂ Blends in a Porous Burner to Fluctuations in Fuel Flow—an Experimental Investigation

Fluctuations in the fuel flow rate may occur practical combustion systems and result flame destabilization. This is particularly problematic lean ultralean modes of burner operation. In this study, response a ceramic porous to fluctuations different blends methane hydrogen investigated experimentally. Prior injection into burner, blend premixed with air at equivalence ratios below 0.275. The streams are measured controlled separately by programmable mass controllers, which impose sinusoidal on rates. To replicate realistic rate, period oscillations chosen be order minutes. temperature inside foam using five thermocouples located center working section burner. embedded media imaged while modulated. Analysis pictures traces shows that forced oscillation mixture leads movement within found act accordance flows for both CH4(90%)–H2(10%) CH4(70%)–H2(30%) mixtures. However, mixtures noted rather insensitive fluctuation modulation amplitude 30% steady flow. For mixture, medium can modulated between 0 without any noticeable