Injector assembly for a gas turbine and aircraft
An injector assembly for a gas turbine for introducing a gaseous fuel, liquid fuel and air into a combustion chamber, includes an injector shaft and an injector main body aligned along an injector longitudinal axis. The injector main body includes a first gas duct arranged centrally on the injector longitudinal axis, for introducing a gas flow into the combustion chamber; an air duct arranged radially around the outside of the first gas duct, and a liquid fuel injection arranged radially around the first gas duct for introducing the liquid fuel into the combustion chamber. The injector assembly introduces the gaseous fuel. The injector assembly is switchable between two configurations during operation: in a first configuration, air flows through the first gas duct, as an air injection; in a second configuration, the gaseous fuel flows through, as a gas fuel injection.
1 . An injector assembly for a gas turbine, configured for introducing a gaseous fuel and a liquid fuel and air into a combustion chamber, comprising:
an injector shaft, and
an injector main body aligned along an injector longitudinal axis, wherein the injector main body comprises:
a first gas duct arranged centrally on the injector longitudinal axis to include the longitudinal axis, for introducing a flow of the gaseous fuel or a flow of air into the combustion chamber,
at least one air duct arranged radially around an outside of the first gas duct, and
a liquid fuel injector arranged radially around the first gas duct for introducing the liquid fuel into the combustion chamber,
wherein the injector assembly is also configured to introduce the gaseous fuel, wherein the injector assembly is configured to adopt two, alternative configurations between which the injector assembly can be switched during operation, wherein in a first configuration air flows through the first gas duct, as an air injection, and in a second configuration the gaseous fuel flows through the first gas duct as a gas fuel injection;
a gas fuel ring reservoir arranged downstream of the gas fuel supply line;
wherein the first gas duct comprises, in an upstream end portion, an air inflow opening, which is arranged centrally on the injector longitudinal axis to include the longitudinal axis, and
at least one gas fuel transfer line arranged within the injector main body and extending radially between the gas fuel ring reservoir and the first gas duct,
wherein, in the first configuration the gas fuel transfer line(s) is/are closed and in the second configuration the air inflow opening is closed.
2 . The injector assembly according to claim 1 , and further comprising at least one closing body for switching between the first and second configurations, the at least one closing body being configured such that:
in the first configuration, each of the at least one closing body is radially displaced into a respective one of the at least one gas fuel transfer line to close the respective one of the at least one gas fuel transfer line while opening the air inflow opening; and
in the second configuration, the at least one closing body is positioned radially centrally, in or downstream of the air inflow opening, in the first gas duct to close the air inflow opening while opening the respective one of the at least one gas fuel transfer line.
3 . The injector assembly according to claim 2 , and further comprising:
a closing body duct for each of the at least one closing body, for the gaseous fuel to flow through,
each closing body duct being arranged so that the flow of gaseous fuel cannot pass through the closing body duct in the first configuration and the flow of gaseous fuel can pass through the closing body duct in the second configuration, by the positioning of the respective one of the at least one closing body.
4 . The injector assembly according to claim 3 , and further comprising at least one resilient actuating element for switching between the first and second configurations, the at least one resilient actuating element performing the switch between the first configuration and the second configuration by a spring force in interaction with a compressive force applied by the gaseous fuel.
5 . The injector assembly according to claim 4 , wherein the first configuration forms a rest state in which the at least one resilient actuating element is in a rest position without counteraction of the compressive force; and in the second configuration, the at least one resilient actuating element is adjusted by counteracting the compressive force.
6 . The injector assembly according to claim 5 , wherein the at least one resilient actuating element is arranged to act on each of the at least one closing body.
7 . The injector assembly according to claim 6 , wherein the at least one closing body includes two closing bodies and the at least one gas fuel transfer line includes two gas fuel transfer lines arranged opposite one another across the first gas duct with respect to the injector longitudinal axis, wherein each of the at least one resilient actuating element is fastened at one end to one of the two closing bodies,
wherein, in the first configuration, the two closing bodies are pushed apart radially into the two gas fuel transfer lines by the at least one resilient actuating element, releasing the air inflow opening, and/or
wherein, in the second configuration, the two closing bodies are radially compressed by the compressive force of the gaseous fuel against the spring force of the at least one resilient actuating element, such that the two closing bodies are positioned centrally within the first gas duct in contact with one another.
8 . The injector assembly according to claim 2 , wherein the first gas duct has a smallest flow cross-section at an axial position of the at least one closing body.
9 . The injector assembly according claim 1 , wherein the air duct is formed as a second gas duct running radially directly around the first gas duct, wherein an upstream end of the second gas duct is positioned at, or upstream of, an axial position of an upstream end of the air inflow opening.
10 . The injector assembly according to claim 9 , wherein the first gas duct is arranged in a central body extending coaxially to the injector longitudinal axis within the second gas duct, and further comprising:
the at least one gas fuel transfer line connecting the gas fuel supply line and the first gas duct, the at least one gas fuel transfer line extending radially through the second gas duct, and
further support elements and/or swirl elements extending radially within the second gas duct to hold the central body.
11 . The injector assembly according to claim 10 , wherein the at least one gas fuel transfer line in the second gas duct is shaped and/or clad in a flow optimized manner, wherein the at least one gas fuel transfer line is configured as an additional swirl element.
12 . The injector assembly according to claim 9 , wherein the liquid fuel injector is arranged radially on the outside around the second gas duct and is configured for introducing the liquid fuel at a downstream end of the second gas duct, into an air flow flowing through the second gas duct and/or emerging therefrom, by at least one liquid fuel outlet opening, opening at the downstream end of the second gas duct.
13 . The injector assembly according to claim 1 , wherein the air duct is formed as a second gas duct, and further comprising a third gas duct, and a fourth gas duct, which are arranged radially around the liquid fuel injector, wherein the third gas duct is configured as a radially outer air duct and the fourth gas duct is configured as a radially outermost air duct.
14 . An aircraft having at least one engine comprising the injector assembly according to claim 1 , and having a fuel peripheral comprising at least one tank device for each of the gaseous fuel and the liquid fuel from the respective at least one tank device to the injector assembly, and further comprising at least one fuel valve for controlling the gaseous fuel arranged in the gaseous fuel line and at least one fuel valve for controlling the liquid fuel arranged in the liquid fuel line, wherein when the at least one fuel valve for the gaseous fuel is closed, with interruption of the flow of the gaseous fuel, the injector assembly assumes the first configuration and when the at least one fuel valve for the gaseous fuel is opened, the injector assembly assumes the second configuration.
15 . The injector assembly to claim 1 , wherein the first configuration, the gaseous fuel is prevented from flowing through the first gas duct, and while in the second configuration, air is prevented from flowing through the first gas duct.
16 . The injector assembly to claim 10 , wherein in the first configuration, the gaseous fuel is prevented from flowing through the first gas duct, and while in the second configuration, air is prevented from flowing through the first gas duct.
17 . An injector assembly for a gas turbine, configured for introducing a gaseous fuel and a liquid fuel and air into a combustion chamber, comprising:
an injector shaft, and
an injector main body aligned along an injector longitudinal axis,
wherein the injector main body comprises:
a first gas duct arranged centrally on the injector longitudinal axis and including the longitudinal axis, for introducing a flow of the gaseous fuel or a flow of air into the combustion chamber,
at least one air duct arranged radially around an outside of the first gas duct, and
a liquid fuel injector arranged radially around the first gas duct for introducing the liquid fuel into the combustion chamber,
wherein the injector assembly is also configured to introduce the gaseous fuel,
wherein the injector assembly is configured to adopt two alternative configurations between which the injector assembly can be switched during operation,
wherein in a first configuration air flows through the first gas duct, as an air injection, and in a second configuration the gaseous fuel flows through the first gas duct as a gas fuel injection;
wherein the air duct is formed as a second gas duct running radially directly around the first gas duct, wherein an upstream end of the second gas duct is positioned at, or upstream of, an axial position of an upstream end of an air inflow opening at an upstream end of the first gas duct;
wherein the first gas duct is arranged in a central body extending coaxially to the injector longitudinal axis within the second gas duct;
at least one gas fuel transfer line connecting a gas fuel supply line and the first gas duct, the at least one gas fuel transfer line extending radially through the second gas duct, and
further support elements and/or swirl elements extending radially within the second gas duct to hold the central body.
18 . The injector assembly according to claim 17 , wherein in the first configuration, the gaseous fuel is prevented from flowing through the first gas duct, and while in the second configuration, air is prevented from flowing through the first gas duct.