Abstract
Experiments were performed for turbulent premixed flames of methane/CO_2-diluted-air mixture at pressure ranging from atmospheric pressure to high pressure up to 1.0MPa and mixture temperatures of 300K and 573K, which covers the typical operating conditions of premixed-type gas-turbine combustors. Bunsen-type flame was stabilized in a high pressure chamber and OH-PILF visualization was performed. Using the OH-PLIF images, contours of the mean progress variable were determined assuming flamelet regime, and turbulent burning velocity and time-and-space-averaged fuel consumption rate in the flames were measured. Results showed that the time-and-space averaged fuel consumption rate became small by the CO_2 dilution. It is mainly due to the increase in the volume of flame region, meaning suitable conditions for eliminating the combustion instability in premix-type gas turbine combustors.
