Stability of Hydrogen/Hydrocarbon Blended Fuel Flames

An experimental and numerical investigation is presented to delineate the effects on the stability of natural gas jet flames when hydrogen is added. It is observed that the flame liftoff height decreases nonlinearly with the addition of hydrogen in a natural gas flame. Blowout velocity sharply increases with the increase of hydrogen content in the mixture. It is evident that hydrogen fuel dominates the stability behavior of the mixed fuel. The turbulent mixing rate of nonreacting hydrogen/hydrocarbon hybrid fuel was computed numerically. The Favre averaged Navier-Stokes equations were solved numerically, and the local concentrations of hydrogen and hydrocarbon fuels were calculated for different inlet mixture conditions. The significance of the local concentration on the flame stability mechanism is presented. (Author)