Effects of flue gas recirculation on the premixed oxy-methane flames in atmospheric condition. (September 2015)

• Record Type: Journal Article
• Authors: Li, Yueh-Heng; Chen, Guan-Bang; Lin, Yi-Chieh; Chao, Yei-Chin
• Is Part Of: Energy. Volume 89(2015)
• Page Start: 845
• Page End: 857
• Publication Date: 2015-09
• Subjects: Oxy-fuel -- Oxy-combustion -- Fluegas -- Flame structure -- Laminar burning velocity; Power resources -- Periodicals; Power (Mechanics) -- Periodicals; Energy consumption -- Periodicals; 333.7905
• DOI: 10.1016/j.energy.2015.06.032
• Languages: English
• ISSNs: 0360-5442

Abstract

Abstract: This numerical study investigates the flame characteristics of premixed methane with various dilutions in order to simulate oxy-combustion of hydrocarbon fuels with flue gas recirculation system. In general, a recirculated flue gas consists of high concentration CO2 /H2 O and high gas temperature. The effect of various diluent gases on laminar burning velocity and adiabatic flame temperature is discussed via using Chemkin-pro simulation. By observing the resultant flame temperature and species concentration profiles one can identify that the flame front shifts, and the concentration profiles of major chemical reaction radicals varies, indicating the change of flame structure and flame chemical reaction paths. The dominant initial consumption reaction step of methane shifts from R53 (H + CH4 CH3 + H2 ) to R98 (OH + CH4 CH3 + H2 O) when nitrogen is replaced by the recirculated gases. H and OH radical concentration would be influenced in various diluent gas cases, so that it leads to affect hydrogen formation and methane consumption. It is because that the chemical effects of the recirculated gases change the chemical reaction of the oxy-fuel combustion, and further affect reaction rate, species and radical concentrations. Highlights: The effect of various dilutions in oxy-fuel combustion is numerically examined. Measured and simulated burning velocities of oxy-methane combustion are consistent. Using fictitious species is to examine the chemical effect of oxy-methane combustion. Flame structures of oxy-methane in N2, CO2, H2 O and fluegas dilution are compared.