Numerical simulation was conducted to investigate the effect of the premixed section exit angle on swirling premixed combustion characteristics of a gas turbine combustor

and the flow field

temperature field

CH4 distribution and NO_x generation characteristics in the combustion chamber at different exit angles of the premixed section were analyzed. The results show that

as the angle of exit of the premixed section increases

the axial velocity decreases

the reflux velocity reduces

the recirculation zone at the exit of the premixed zone broadens

the area of the total recirculation zone decreases

the angular recirculation zone disappears gradually

and the reflow intensity weakens. CH4 gradually diffused into the corner recirculation zone

the length of the flame extended

the range of the high-temperature zone expanded

and the NO_x mole fraction at the outlet gradually increased

while the CO mole fraction changed the opposite. In the case with the same inlet parameters

the most reasonable premixed section exit angle is 12°.