Effect of fuel injector on the performance of a gas turbine combustor

The influence of fuel injector on the performance parameters of a can-type combustor were examined experimentally using LPG fuel and at atmospheric conditions. The first injector is a typical 45° conical injector with 6 holes on its curved surface, and the second injector is a swirl injector with 6 holes whose axes are not parallel with each other and are oriented at 19° in respect to the combustor’s axis. Three operating points were selected, and temperature distribution in the intermediate zone of the combustor and at the outlet section of the combustor was obtained using k-type thermocouples. Results reveal that the swirl injector provides better air-fuel mixing (due to the tangential motion forced on the fuel flow), more uniform temperature distribution in the combustor, lower liner temperature, higher combustion efficiency, and lower pattern factor. In addition, stability curve was also obtained for two configurations, and the results showed that the conical injector provides better stability for the combustor and is operable in a wider range of operating conditions. The results also show that the flame is generally shaped near the walls and the vicinity of the combustor’s liner and outlet walls are in contact with hot gases which reduces the combustor’s lifetime.