Combustion Mechanism Of The Methane Fuel And Its Application In Gas Turbine

The ignition characteristics of methane fuel were experimental measured in a chemicalshock tube, and the effects of initial temperature, pressure and equivalence ratio on theignition characteristics of methane fuel were analyzed. The results show that the correlationfor the logarithm of the ignition delay time of the methane fuel and the reciprocal initialtemperature is linear, and with the increase of initial temperature, the ignition delay time isshorten. The effect of equivalence ratio on the ignition delay time of methane fuel is notobvious. With the increase of initial pressure, the ignition delay time of methane fuel is alsoshorten. The ignition characteristics of methane fuel were simulated by adopting three kindsof chemical kinetic model of methane fuel. The results show that Gri₃.0reaction kineticmodel can predict ignition characteristics of methane fuel well under different conditions. Thecombustion characteristics of methane fuel were experimental studied in a constant volumecombustion reactor, and the effects of initial temperature, pressure and equivalence ratio on itscombustion characteristics were analyzed. The results show that with initial pressureincreasing and initial temperature decreasing, the markstein length is shortening remarkablyand unstretched laminar flame propagation velocity and laminar burning velocity are reducedobviously. With the increase of equivalent ratio, markstein length is prolonged obviously,unstretched laminar flame propagation velocity and the laminar burning velocity increasedfirstly and then decreased, and reach the maximum value at equivalence ratio is1.1. Thecombustion characteristics of methane fuel were simulated by adopting three kinds ofchemical kinetic model of methane fuel. The results show that Gri₃.0reaction kinetic modelcan predict combustion characteristics of methane fuel well under different conditions.Coupling Gri₃.0chemical reaction kinetic model of methane fuel into the computationalfluid dynamics software, the combustion processes of a heavy duty gas turbine used methanefuel were simulated and the computed results were compared with experimental results. Theresults show that the velocity field, temperature field, the concentration fields of the reactants,products, and the main intermediate components calculated by adopting the reaction kinetic model of methane fuel can better reflect the actual burning situations of this gas turbinecombustor, and the computed outlet temperature distributions agreed well with theexperimental data.