Swirler with Upstream Fuel Injection to Reduce the Combustion Dynamics Caused by Air-Fuel Ratio Fluctuations

Swirler with Upstream Fuel Injection to Reduce the Combustion Dynamics tio Fluctuations

Caused by Air-Fuel Ra

Idea: Kexin Liu, Ph.D., GB-Lincoln

The idea is directed to a combustor of a gas turbine engine. Fluctuations in the equivalen the air/fuel mixture are one of the main causes for gas turbine combustion dynam fluctuations are induced by upstream traveling acoustic waves from the combustion consequence, the heat release rate pulses and the pressure is oscillating, form
feedback loop. To reduce the fluctuations of the equivalence ratio, a concept is
fuel is injected into the combustion air in a very upstream location, as shown in Figure 1 (b method the pressure oscillation can be suppressed efficiently, compared to the trad configuration shown in Figure 1 (a). Up to now, the modification of the fuel injectio applied to most of the modern gas turbines.

In the following a swirler and a plate with slots for an upstream fuel injection is prop
the concept mentioned before. The proposed arrangement is shown in Figure 2. T
enters the swirler passage through the slots of the proposed plate. The proposed s
Figure 3. The swirler has a longer passage than a state of the art swirler. If a single
ideal fuel injection positions are on the side wall of the swirler, as shown in Figure configuration is used, for example gaseous and liquid, there are two different varian injection positions. One variant is that both fuels are injected on the side wall of the
two holes are used, one for the gas and the other for the liquid fuel. In a second va
injected on the base wall of the swirler while the liquid fuel is injected on the sid
injection points on the base wall are used, their location should be in an upstream position of swirler passages. The proposed plate, shown in Figure 5, is atta

air. The mixture of air and fuel then passes the swirler passage and is burned in

      ce ratio of ics. These

    cha...