Adiabatic laminar burning velocities of CH4 + H2 + air flames at low pressures

Measurements of the adiabatic burning velocity of methane + hydrogen + air flames are presented. The hydrogen content in the fuel was varied from 0 to 20%. Non-stretched flames were stabilized on a perforated plate burner from 20 to 100 kPa. Equivalence ratio was varied from 0.8 to 1.4. The Heat Flux method was used to determine burning velocities under conditions when the net heat loss of the flame is zero. Adiabatic burning velocities of CH4 + H2 + air mixtures were found in good agreement with the literature results at atmospheric pressure. Also lowpressure measurements in CH4 + air flames performed earlier were accurately reproduced. The effects of enrichment by hydrogen on laminar burning velocity at low pressures have been studied for the first time.