FINITE CHEMICAL KINETIC EFFECTS IN A SUBSONIC TURBULENT HYDROGEN FLAME

An experimental study is presented that shows departures from chemical equilibrium in a hydrogen-air flame, which is often erroneously considered to have an infinitely fast chemical rate and therefore to be at chemical equilibrium. These departures from chemical equilibrium are measured with nonintrusive laser diagnostics. The authors vary the Damkohler number by adjusting either the aerodynamic conditions or the chemical rate. In the first case, a range of Reynolds numbers is explored - Re equals 8500, Re equals 17,000, and Re equals 20,000 - using the same fuel. The experimental results show a dramatic effect of the Reynolds number on the extent of departure from the limit of chemical equilibrium.