Patent Description:
Torch ignitors can be used in lieu of spark ignitors to provide an ignition source for combustors located in gas turbine engines. Torch ignitors provide a flame to the combustor of a gas turbine engine as an ignition source rather than the electric current provided by spark ignitors. Consequently, torch ignitors can provide a larger target for fuel injectors within the combustor, allowing for utilization of a greater range of fuel injector designs. Traditionally, torch ignitors include a single torch or flame jetting into the combustor of the gas turbine engine to ignite the fuel sprayed from the fuel nozzles within the gas turbine engine. <CIT> relates to igniting devices. <CIT> relates to combustion apparatus. <CIT> relates to a flame igniter.

According to one aspect of the disclosure, a system as in claim <NUM> is disclosed.

According to another aspect of the disclosure, a method of igniting fuel within a combustor of a gas turbine as in claim <NUM> is disclosed.

<FIG> is a front view of torch ignitor system <NUM>. <FIG> is a side view of torch ignitor system <NUM>. <FIG> is a perspective view of torch ignitor system <NUM>. <FIG> is a cross-sectional view of torch ignitor system <NUM> within a gas turbine engine. <FIG> is a close-up cross-sectional view of a portion of torch ignitor system <NUM> within the gas turbine engine. <FIG> is a side cross-sectional view of an operational torch ignitor system <NUM> within the gas turbine engine (with combustion chamber <NUM> removed for clarity). <FIG> will be discussed together. Torch ignitor system <NUM> is a continuous ignition device used to ignite a fuel and air mixture within a combustor of a gas turbine engine (not shown). Torch ignitor system <NUM> includes torch ignitor <NUM>, combustion chamber <NUM>, manifold <NUM>, and torch nozzles <NUM>. Torch ignitor <NUM> includes housing <NUM>, hot surface ignitors <NUM>, fuel inlet <NUM> (<FIG>), and air inlet <NUM> (<FIG>). Combustion chamber <NUM> includes first end 14A, second end 14B, outer body <NUM>, vanes <NUM>, and quenching aperture <NUM> (<FIG>). Manifold <NUM> includes (shown in <FIG>) outer wall <NUM>, interior <NUM>, and vanes (not shown). Torch nozzles <NUM> are coupled to and extend outwards from manifold <NUM>.

Torch ignitor <NUM> includes housing <NUM>, hot surface ignitors <NUM>, fuel inlet <NUM> (<FIG>), and air inlet <NUM> (<FIG>). Housing <NUM> is the main body portion of torch ignitor <NUM> that provides structure for the other components of torch ignitor <NUM> to be coupled. Housing <NUM> can be constructed from a nickel-chromium alloy, a nickel-chromium-iron-molybdenum alloy, a <NUM>-series stainless steel alloy, or other high-temperature high-strength metallic or nonmetallic material that can withstand the high temperature environment within a gas turbine engine. Hot surface ignitors <NUM> extend through and are coupled to housing <NUM> of torch ignitor <NUM>. More specifically, hot surface ignitors <NUM> are coupled to housing <NUM> such that a portion of each of the hot surface ignitors <NUM> is within housing <NUM> and another portion of each of the hot surface ignitors <NUM> is outside of housing <NUM>. Hot surface ignitors <NUM> are electrical resistance heating elements that are configured to receive a positive and negative electric charge in the form of an electric current to increase the temperature of the element due to the resistive properties of the electrical resistance heating elements. In some examples, hot surface ignitors <NUM> can be constructed from a ceramic material with resistive properties allowing hot surface ignitors <NUM> to achieve a temperature that exceeds the ignition temperature of a fuel and air mixture within torch ignitor system <NUM> of the gas turbine engine. In the embodiment shown there are three hot surface ignitors <NUM>, but in another embodiment, there can be more than or less than three hot surface ignitors <NUM>.

Fuel inlet <NUM> (<FIG>) is coupled to an upper side portion of housing <NUM> at an oblique angle through standard attachment techniques, such as a mating threaded engagement. Fuel inlet <NUM> provides a flow path for fuel to enter housing <NUM> of torch ignitor <NUM> to be ignited by hot surface ignitors <NUM>. The portion of fuel inlet <NUM> positioned outside of housing <NUM> is configured to receive fuel from a fuel source and the portion of fuel inlet <NUM> positioned within housing <NUM> is configured to distribute or spray the received fuel into housing <NUM>. In the embodiment shown, fuel inlet <NUM> receives fuel from the main fuel source that supplies fuel to the gas turbine engine. In another embodiment, fuel inlet <NUM> can receive fuel from a separate fuel source other than the main fuel source that supplies fuel to the gas turbine engine. Air inlet <NUM> is positioned within and coupled to housing <NUM>. Air inlet <NUM> is configured to receive pressurized air from an air source within the gas turbine engine and distribute the pressurized air into housing <NUM>. More specifically, air inlet <NUM> is configured to receive the pressurized air and meter or regulate the amount of air entering housing <NUM> to ensure the proper ratio of fuel and air is mixed within housing <NUM> and ignited by hot surface ignitors <NUM>. Further, the pressurized air entering housing <NUM> through air inlet <NUM> is utilized to atomize the fuel entering housing <NUM> through fuel inlet <NUM> to produce an efficient burn of the fuel and air mixture, as compared to non-atomized fuel. Torch ignitor <NUM> is configured to receive fuel from a fuel source and air from an air source, mix the fuel and air into a fuel and air mixture, and ignite the fuel and air mixture as it enters combustion chamber <NUM>. As shown in <FIG>, a lower portion of torch ignitor <NUM> is adjacent and coupled to combustion chamber <NUM> to distribute the ignited fuel and air mixture into combustion chamber <NUM>.

Combustion chamber <NUM> is a tube, passage, channel, or the like including a hollow center portion configured to allow fluid, such as an ignited fuel and air mixture, to flow through combustion chamber <NUM>. In the embodiment shown, combustion chamber <NUM> is a round tube with a hollow center portion. In another embodiment, combustion chamber <NUM> can be a tube of any geometric shape with a hollow center portion allowing a fluid, such as an ignited fuel and air mixture, to flow through the hollow center portion. Combustion chamber <NUM> can be constructed from a nickel-chromium alloy, a nickel-chromium-iron-molybdenum alloy, a <NUM>-series stainless steel alloy, or other high-temperature high-strength metallic or nonmetallic material that can withstand the high temperature environment within a gas turbine engine. Combustion chamber <NUM> includes first end 14A, second end 14B, outer body <NUM>, vanes <NUM>, and quenching apertures <NUM> (<FIG>).

First end 14A of combustion chamber <NUM> is adjacent and coupled to the lower portion of torch ignitor <NUM>. Second end 14B of combustion chamber <NUM> is adjacent and coupled to manifold <NUM>. Combustion chamber <NUM> is in fluid communication with both torch ignitor <NUM> and manifold <NUM>, fluidly connecting torch ignitor <NUM> to manifold <NUM>. More specifically, combustion chamber <NUM> is configured to provide a flow passage or flow path for the ignited fuel and air mixture to flow from torch ignitor <NUM>, through combustion chamber <NUM>, and into manifold <NUM>. As such, combustion chamber <NUM> is configured to allow the ignited fuel and air mixture to flow from torch ignitor <NUM> directly into manifold <NUM> of torch ignitor system <NUM>. As shown in <FIG>, combustion chamber <NUM> includes a larger diameter portion adjacent first end 14A and a smaller diameter portion adjacent second end 14B. The smaller diameter portion adjacent second end 14B is configured to constrict the flow of the ignited fuel and air mixture before the ignited fuel and air mixer enters manifold <NUM>, increasing the pressure and velocity of the ignited fuel and air mixture as it enters manifold <NUM>. In the embodiment shown, combustion chamber <NUM> includes the smaller diameter portion adjacent second end 14B of combustion chamber <NUM>. In another embodiment, combustion chamber <NUM> can have a constant diameter extending from first end 14A to second end 14B of combustion chamber <NUM>.

Manifold <NUM> is a circular tube, passage, channel, or the like including a hollow center portion configured to allow fluid, such as an ignited fuel and air mixture, to flow through manifold <NUM>. In other words, manifold <NUM> is a torus shaped tube including a round cross-section that is configured to allow an ignited fuel and air mixture to flow through a hollow center portion of manifold <NUM>. In the embodiment shown, manifold <NUM> is a round tube with a hollow center portion. In another embodiment, manifold <NUM> can be a tube with a cross-section of any geometric shape (e.g. square, triangular, oval, trapezoidal, etc.) including a hollow center portion allowing a fluid, such as an ignited fuel and air mixture, to flow through the hollow center portion. In yet another embodiment, manifold <NUM> can include a gradually decreasing cross-sectional area extending from the location where manifold <NUM> interfaces with combustion chamber <NUM> to the location positioned farthest away from the location where manifold <NUM> interfaces with combustion chamber <NUM>. A gradually decreasing cross-sectional area of manifold <NUM> ensures more uniform velocities of the ignited fuel and air mixture flowing through manifold <NUM>, as portions of the ignited fuel and air mixture exit from manifold <NUM> through torch nozzles <NUM>. Manifold <NUM> can be constructed from a nickel-chromium alloy, a nickel-chromium-iron-molybdenum alloy, a <NUM>-series stainless steel alloy, or other high-temperature high-strength metallic or nonmetallic material that can withstand the high temperature environment within a gas turbine engine. Manifold <NUM> includes outer wall <NUM> and interior <NUM> (<FIG>).

Outer wall <NUM> of manifold <NUM> is the main body portion or structural portion of manifold <NUM>. Outer wall <NUM> includes an inner skin and an outer skin, with the volume within the inner skin defining interior <NUM> of manifold <NUM>. Interior <NUM> is the space or volume within manifold <NUM> in which an ignited fuel and air mixture will be contained and flow through during operation of torch ignitor system <NUM>. Outer wall <NUM> is a component of manifold <NUM>, and thus can be constructed from a nickel-chromium alloy, a nickel-chromium-iron-molybdenum alloy, a <NUM>-series stainless steel alloy, or other high-temperature high-strength metallic or nonmetallic material that can withstand the high temperature environment within a gas turbine engine.

Torch nozzles <NUM> are coupled to outer wall <NUM> of manifold <NUM> and extend outwards from outer wall <NUM> in the opposite direction as interior <NUM> of manifold <NUM>. In the embodiment shown, torch nozzles <NUM> are coupled to manifold <NUM> through standard connection techniques, such as brazing, welding, etc. In another embodiment, torch nozzles <NUM> and manifold <NUM> can be of uniform construction, such that torch nozzles <NUM> and manifold <NUM> are a single-piece material manufactured to form a monolithic component (i.e. through additive manufacturing techniques). Torch nozzles <NUM> are fluidly connected with interior <NUM> of manifold <NUM> and torch nozzles <NUM> are configured to expel or jet an ignited fuel and air mixture from interior <NUM> of manifold <NUM> outwards through torch nozzles <NUM>. In other words, torch nozzles <NUM> are configured to control the direction and velocity of an ignited fuel and air mixture as it exits interior <NUM> of manifold <NUM> and enters a combustor of the gas turbine engine.

In the embodiment shown, there are twelve torch nozzles <NUM> spaced equidistant about outer wall <NUM> of manifold <NUM>. In another embodiment, there can be more than or less than twelve torch nozzles <NUM> spaced equidistant about outer wall <NUM> of manifold <NUM>, the number of torch nozzles <NUM> can vary depending on the pressure and flow characteristics within torch ignitor system <NUM>. Further, in the embodiment shown, torch nozzles <NUM> extend from outer wall <NUM> at about a <NUM>-degree angle. In another embodiment, torch nozzles <NUM> can extend from outer wall <NUM> within an angle range of <NUM> degrees to <NUM> degrees. Torch nozzles <NUM> can be constructed from a nickel-chromium alloy, a nickel-chromium-iron-molybdenum alloy, a <NUM>-series stainless steel alloy, or other high-temperature high-strength metallic or nonmetallic material that can withstand the high temperature environment within a gas turbine engine.

As shown in <FIG>, torch ignitor system <NUM> is positioned within a gas turbine engine including high-pressure case <NUM>, high-pressure compressor region <NUM>, fuel nozzles <NUM>, and combustor <NUM>. Combustor <NUM> includes combustor liner <NUM> defining the external walls and an internal chamber of combustor <NUM>. Combustor <NUM> also includes combustor outlet <NUM> which is utilized to expel an ignited fuel and air mixture from combustor <NUM> to be utilized by the gas turbine engine to power the turbine section of the gas turbine engine. In operation, air is compressed within high-pressure compressor region <NUM> to create high-pressure air, the high-pressure air flows from high-pressure compressor region <NUM> into combustor <NUM> and mixes with fuel spraying from fuel nozzles <NUM> into combustor <NUM>, the fuel and air mixture is ignited by torch ignitor system <NUM>, and then the ignited fuel and air mixture is expelled through combustor outlet <NUM> to be utilized by the gas turbine engine.

Torch ignitor system <NUM> is positioned at least partially within high-pressure case <NUM> of the gas turbine engine. High-pressure compressor region <NUM>, fuel nozzles <NUM>, and combustor <NUM> are positioned within and fully contained by high-pressure case <NUM>. More specifically, a portion of torch ignitor <NUM> is positioned within high-pressure case <NUM> and another portion of torch ignitor <NUM> is positioned outside of high-pressure case <NUM>. In contrast, combustion chamber <NUM>, manifold <NUM>, and torch nozzles <NUM> of torch ignitor system <NUM> are positioned within and fully contained by high-pressure case <NUM>. In addition, combustion chamber <NUM> and manifold <NUM> are positioned adjacent high-pressure compressor region <NUM>, fuel nozzles <NUM>, and combustor <NUM> of the gas turbine engine. In some embodiments, combustion chamber <NUM> and manifold <NUM> are positioned between high-pressure compressor region <NUM> and combustor <NUM> of the gas turbine engine. In the embodiment shown, torch ignitor <NUM> is positioned partially within high-pressure case <NUM> and partially outside of high-pressure case <NUM>. In another embodiment, torch ignitor <NUM> can be positioned fully within high-pressure case <NUM> of the gas turbine engine. The remaining disclosure will focus on the embodiment in which torch ignitor <NUM> is positioned partially within high-pressure case <NUM> and partially outside of high-pressure case <NUM>, as shown in <FIG>.

As best shown in <FIG>, combustion chamber <NUM> includes second end 14B, outer body <NUM>, and vanes <NUM>. Second end 14B of combustion chamber <NUM> is coupled to manifold <NUM> and second end 14B fluidly connects combustion chamber <NUM> to manifold <NUM>. In one example, combustion chamber <NUM> can be rigidly coupled to manifold <NUM> to secure combustion chamber <NUM> to manifold <NUM>. In another example, combustion chamber <NUM> can be coupled to manifold <NUM> through a sliding joint engagement, allowing combustion chamber <NUM> and manifold <NUM> to move with respect to each other, accounting for different thermal expansion characteristics of combustion chamber <NUM> and manifold <NUM>. Outer body <NUM> of combustion chamber <NUM> is the outer structure or outer body of combustion chamber <NUM>. In the embodiment shown, outer body <NUM> includes vanes <NUM> positioned within and throughout outer body <NUM> of combustion chamber <NUM>. More specifically, outer body <NUM> includes an inner and outer skin with a plurality of vanes <NUM> positioned between the inner and outer skin. The plurality of vanes <NUM> can be oriented such that a fluid flow path exists between the inner and outer skin, allowing a fluid (i.e. cooling air) to flow through the outer walls and past the plurality of vanes <NUM>. In an example, cooling air received from the gas turbine engine can flow past vanes <NUM> and remove heat from combustion chamber <NUM>, thereby cooling combustion chamber <NUM> in the process. Cooling combustion chamber <NUM> can prevent deformation or damage to combustion chamber <NUM>, extending the useful life of combustion chamber <NUM> within torch ignitor system <NUM>.

In the embodiment shown in <FIG>, vanes <NUM> are only shown within a portion of outer body <NUM> of combustion chamber <NUM>. In another embodiment, vanes <NUM> can be positioned within all of outer body <NUM> of combustion chamber <NUM>, such that vanes <NUM> extend to the intersection of combustion chamber <NUM> and manifold <NUM>. In an embodiment including vanes <NUM>, combustion chamber <NUM> can be manufactured using additive manufacturing technology to produce the intricate or complex geometry of vanes <NUM> within outer body <NUM> of combustion chamber <NUM>. In another embodiment including vanes <NUM>, combustion chamber <NUM> can be manufactured using standard manufacturing techniques to produce the intricate or complex geometry of vanes <NUM>. In an embodiment without vanes <NUM>, combustion chamber <NUM> can be manufactured using standard manufacturing techniques.

Although not shown or specifically described, it is to be understood that manifold <NUM> can include vanes within an inner and outer skin of outer wall <NUM> similar to vanes <NUM> within outer body <NUM> of combustion chamber <NUM>. Vanes within outer wall <NUM> of manifold <NUM> could be utilized to cool manifold <NUM> to prevent deformation or damage to manifold <NUM>, extending the useful life of manifold <NUM> within torch ignitor system <NUM>. In an embodiment including vanes within outer walls <NUM>, manifold <NUM> can be manufactured using additive manufacturing technology to produce the intricate or complex geometry of the vanes within outer wall <NUM>. In an embodiment without vanes, manifold <NUM> can be manufactured using standard manufacturing techniques. In another embodiment, manifold <NUM> could be cooled by including a tube or shell fully surrounding the outer skin of outer wall <NUM> of manifold <NUM>. The tube or shell could be offset from and concentric with outer wall <NUM> of manifold <NUM>, creating a space between outer wall <NUM> and the tube or shell. The space between the two components could be utilized to flow cooling air through to remove heat from manifold <NUM>. In an example, cooling air from a pressurized air source within the gas turbine engine could enter the space between the tube or shell and manifold <NUM> at a location <NUM> degrees from combustion chamber <NUM> and flow through the space, removing heat from manifold <NUM> as the air flows through the space. In another example, cooling air from a pressurized air source within the gas turbine engine could enter the space between the tube or shell and manifold <NUM> at any location or angle and flow through the space, removing heat from manifold <NUM> as the air flows through the space.

As shown in <FIG>, combustion chamber <NUM> can also include quenching aperture <NUM> positioned within outer body <NUM> of combustion chamber <NUM>. Quenching aperture <NUM> provides a cooling air flow path that is configured to distribute cooling air within an interior of outer body <NUM> of combustion chamber <NUM>. More specifically, quenching aperture <NUM> is a tube, passage, channel, or the like including a hollow center portion that is configured to receive cooling air from an air source within the gas turbine engine and flow the cooling air into combustion chamber <NUM>. Quenching aperture <NUM> is configured to cool an ignited fuel and air mixture before the ignited fuel and air mixture exits combustion chamber <NUM> and flows into manifold <NUM>. Cooling the ignited fuel and air mixture can prevent melting or other damage to manifold <NUM>. In an example, the ignited fuel and air mixture within combustion chamber <NUM> is about <NUM>,<NUM> degrees Fahrenheit before quenching with cooling air. After quenching with cooling air, the ignited fuel and air mixture can be reduced to a temperature of about <NUM>,<NUM> degrees Fahrenheit, which is a temperature high enough to ignite fuel within combustor <NUM> but also low enough to prevent melting and damage to manifold <NUM> and other components of the gas turbine engine.

During operation of torch ignitor system <NUM>, air from air inlet <NUM> and fuel from fuel inlet <NUM> are dispensed into and mixed (atomizing the fuel) within housing <NUM> of torch ignitor <NUM>. The fuel and air mixture flows from housing <NUM> into first end 14A of combustion chamber <NUM>, where the fuel and air mixture is ignited by hot surface ignitors <NUM> of torch ignitor <NUM>. The ignited fuel and air mixture (a flame or torch) flows from first end 14A to second end 14B of combustion chamber <NUM>, and into manifold <NUM>. Referring to <FIG> and <FIG>, the ignited fuel and air mixture flows through interior <NUM> of manifold <NUM>, following the curvature of the circular tube that constitutes manifold <NUM> until the ignited fuel and air mixture begins to fill the torus shaped interior <NUM> of manifold <NUM>. The ignited fuel and air mixture then exits or jets outward from torch nozzles <NUM> positioned around outer wall <NUM> of manifold <NUM>. In an example, the jet of ignited fuel and air mixture can exit torch nozzles <NUM> at an angle such that the ignited fuel and air mixture is aimed towards centerline CL of each of the fuel nozzles <NUM> to ignite the central recirculation zones of fuel nozzles <NUM>. In another example, the jet of ignited fuel and air mixture can exit torch nozzles <NUM> at a tangential angle across multiple torch nozzles <NUM> to simultaneously ignite multiple torch nozzles <NUM> with a single jet of ignited fuel and air mixture. The ignited fuel and air mixture jets from each of torch nozzles <NUM> into combustor <NUM> adjacent each of the fuel nozzles <NUM> of the gas turbine engine, igniting the fuel dispensing from each of fuel nozzles <NUM> into combustor <NUM> of the gas turbine engine.

As such, in the embodiment shown, torch ignitor system <NUM> is configured to provide an ignited fuel and air mixture adjacent each of the fuel nozzles <NUM> of the gas turbine engine to easily and efficiently ignite the fuel dispensing from each of the fuel nozzles <NUM> within the gas turbine engine. In another embodiment, manifold <NUM> can include a reduced number of torch nozzles <NUM> strategically placed to ignite more than one fuel nozzle <NUM> simultaneously. In one example, manifold <NUM> could include a torch nozzle <NUM> for every other fuel nozzle <NUM> of the gas turbine engine, such that each torch nozzle <NUM> would ignite two fuel nozzles <NUM> of the gas turbine engine. In another example, manifold <NUM> could include one torch nozzle <NUM> for each quadrant of combustor <NUM>, such that each torch nozzle <NUM> would ignite two or more fuel nozzles <NUM> of the gas turbine engine. In yet another example, each torch nozzle <NUM> could be incorporated into a central portion (along centerline CL) of each fuel nozzle <NUM> of the gas turbine engine to ignite the fuel dispensing from each fuel nozzle <NUM> of the gas turbine engine. Therefore, torch ignitor system <NUM> is configured to ignite multiple, or all, fuel nozzles <NUM> of the gas turbine engine simultaneously, allowing for an easier and more efficient startup of combustor <NUM> of the gas turbine engine.

In the embodiment shown in <FIG>, the gas turbine engine includes a single torch ignitor <NUM> and combustion chamber <NUM> within torch ignitor system <NUM>. In another embodiment, the gas turbine engine can include two or more torch ignitors <NUM> and combustion chambers <NUM> within torch ignitor system <NUM>. In an example, torch ignitor system <NUM> could include a second torch ignitor <NUM> and second combustion chamber <NUM> positioned halfway around manifold <NUM>, such that the second torch ignitor <NUM> and second combustion chamber <NUM> are positioned <NUM> degrees around manifold <NUM> from the first torch ignitor <NUM> and first combustion chamber <NUM>, respectively. Including two or more torch ignitors <NUM> and combustion chambers <NUM> ensures that the ignited fuel and air mixture fully surrounds and flows through the entire interior <NUM> of manifold <NUM>. Additionally, in the embodiment shown in <FIG>, manifold <NUM> is positioned between high-pressure compressor region <NUM> and combustor <NUM> and the ignited fuel and air mixture jets into combustor <NUM> adjacent fuel nozzles <NUM>. In another embodiment, manifold <NUM> could surround the outer surface of combustor liner <NUM> of combustor <NUM> and torch nozzles <NUM> could extend into combustor <NUM> halfway down combustor <NUM>. In yet another embodiment, manifold <NUM> could surround the outer surface of combustor liner <NUM> of combustor <NUM> and torch nozzles <NUM> could extend into combustor <NUM> adjacent a corner of combustor liner <NUM>. In yet another embodiment, manifold <NUM> could surround the outer surface of combustor liner <NUM> of combustor <NUM> and torch nozzles <NUM> could extend into combustor <NUM> adjacent combustor outlet <NUM>. In each embodiment, torch ignitor system <NUM> is configured to ignite fuel dispensing from fuel nozzles <NUM> into combustor <NUM> of the gas turbine engine.

Further, in the embodiment shown, torch ignitor system <NUM> is configured to ignite fuel dispensing from fuel nozzles <NUM> of a single annular combustor <NUM>. In another embodiment, torch ignitor system <NUM> can be used with multiple can combustors with each can combustor having a torch nozzle <NUM> extending into the can combustor to ignite the fuel dispensing into the can combustor. For example, a gas turbine engine could include six separate can combustors and each can combustor could include a torch nozzle <NUM> extending into the can combustor to ignite the fuel dispensing into the can combustor. As such, torch ignitor system <NUM> can simultaneously ignite fuel within multiple can combustors of a gas turbine engine.

<FIG> is a front view of second torch ignitor system <NUM>' with split manifold <NUM>'. The components and functionality of the components of second torch ignitor system <NUM>' are nearly identical as torch ignitor system <NUM> described in <FIG>. Therefore, to avoid redundant disclosures, each component of second torch ignitor system <NUM>' will not be described in detail and only the differences between second torch ignitor system <NUM>' and torch ignitor system <NUM> will be described. As shown in <FIG>, manifold <NUM>' differs from manifold <NUM> of torch ignitor system <NUM> (<FIG>) in that manifold <NUM>' is split near the bottom of manifold <NUM>' and caps <NUM> cover the split in manifold <NUM>'. More specifically, manifold <NUM>' is split or separated at a location positioned <NUM> degrees around manifold <NUM>', with respect to combustion chamber <NUM>' and the location where an ignited fuel and air mixture enters manifold <NUM>'. Caps <NUM> are positioned to cover the interior opening of manifold <NUM>' at the split location, preventing the ignited fuel and air mixture from escaping or jetting through the split. Caps <NUM> can be constructed from the same or similar material as manifold <NUM>'. The split in manifold <NUM>' and caps <NUM> are configured to prevent excess fuel and/or debris from settling in the bottom farthest portion of manifold <NUM>', away from combustion chamber <NUM>'. The split in manifold <NUM>' and caps <NUM> prevent settling of debris and also force any excess fuel and/or debris to expel or jet outwards from the last torch nozzle <NUM>, keeping the interior of manifold <NUM>' free of excess fuel and/or debris. Keeping the interior of manifold <NUM>' clean reduces the chances of torch nozzles <NUM>' becoming clogged and ensures second torch ignitor system <NUM>' remains in a safe operational state.

In the embodiment shown, manifold <NUM>' includes a split positioned <NUM> degrees around manifold <NUM>', with respect to second end 14B' of combustion chamber <NUM>'. In another embodiment, manifold <NUM>' can include a split positioned at any location or angle around manifold <NUM>', with respect to second end 14B' of combustion chamber <NUM>'. In an example, second end 14B' of combustion chamber <NUM>' can be positioned tangentially to manifold <NUM>' and the flame or torch exiting second end 14B' can have a tangential entry into manifold <NUM>'. In this example, manifold <NUM>' can include a split adjacent one side of second end 14B' of combustion chamber <NUM>', such that the flame or torch flows approximately <NUM> degrees around manifold <NUM>' before reaching cap <NUM> covering the split in manifold <NUM>'. Although cap <NUM> is described in this example as being positioned at a specific angle, it is to be understood that cap <NUM> can be positioned at any angle about manifold <NUM>'. The angle in which cap <NUM> is positioned about manifold <NUM>' varies depending on many factors, such as the angle that combustion chamber <NUM>' is coupled to manifold <NUM>', the ignited fuel and air flow characteristics within torch ignitor system <NUM>', and the pressure in which torch ignitor system <NUM>' is operated, among other variables.

Torch ignitor system <NUM> offers many advantages for a gas turbine engine, as compared to traditional spark ignitors, that will be appreciated by those familiar with ignition techniques of gas turbine engines. Torch ignitor system <NUM> flows the torch or flame (ignited fuel and air mixture) through manifold <NUM>, allowing the torch of flame to simultaneously ignite multiple fuel nozzles of combustor <NUM>. In turn, this allows the gas turbine engine to have a softer start for all fuel nozzles <NUM>, as compared to a traditional spark ignitor. A softer start for the gas turbine engine means the torch or flame can ignite the fuel within combustor <NUM> and start the gas turbine engine with less pressure and less atomization of the fuel spraying into combustor <NUM>, compared to traditional spark ignitors. In contrast, previous gas turbine engines utilizing traditional spark ignitors require a high-pressure environment to ignite the fuel within combustor <NUM>. The softer start, as compared to traditional spark ignitors, is useful at re-igniting the gas turbine engine at high altitudes if the gas turbine engine were to be extinguished. Torch ignitor system <NUM> including manifold <NUM> provides a constant flame or torch to multiple fuel nozzles <NUM>, allowing torch ignitor system <NUM> to ignite multiple fuel nozzles <NUM> simultaneously. The redundancy of flames or torches igniting the fuel dispensing from fuel nozzles <NUM> provides a more stable and overall better ignition system because multiple flames are available to ignite the atomized fuel within the gas turbine engine. As such, torch ignitor system <NUM> is a safer and more reliable ignition system than traditional spark ignitor systems used in gas turbine engines.

Further, torch ignitor system <NUM> provides an independent heat source to combustor <NUM>, which is used to ignite, stabilize, and relight a fuel and air mixture within combustor <NUM>. The continuous flame of torch ignitor system <NUM> is maintained within combustion chamber <NUM> and manifold <NUM> of torch ignitor system <NUM> during operation of the gas turbine engine. Therefore, the isolated continuous flame of torch ignitor system <NUM> is not affected by any blow out or other conditions that may occur within combustor <NUM>, thus stabilizing the gas turbine engine during any disturbances that may occur within combustor <NUM>. The continuous torch or flame of torch ignitor system <NUM> allows torch ignitor system <NUM> to rapidly relight the fuel and air mixture within combustor <NUM> if combustor <NUM> is extinguished. In contrast, traditional spark ignitors can have issues of contamination of the tip of the spark ignitor with burnt debris, causing the spark ignitor to fail to produce a spark to ignite the fuel and air mixture. Therefore, the continuous flame or torch of torch ignitor system <NUM> is a more reliable solution that will have an increased useful lifespan, as compared to traditional spark ignitors, due to minimizing failures and maintenance of the ignitor. Torch ignitor system <NUM> offers many other advantages not specifically described, that will be appreciated by those familiar with ignition techniques of gas turbine engines.

While the invention has been described with reference to an exemplary embodiment(s), it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment(s) disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.

The following are non-exclusive descriptions of possible examples of the present invention.

A torch ignitor system for use with a gas turbine engine including a high-pressure compressor, a high-pressure case, fuel nozzles, and a combustor. The torch ignitor system includes a torch ignitor, a manifold, and a combustion chamber. The torch ignitor is coupled to the high-pressure case of the gas turbine engine. The manifold is positioned within the high-pressure case and the manifold includes a plurality of torch nozzles extending from the manifold into the combustor of the gas turbine engine. The combustion chamber is positioned within the high-pressure case and the combustion chamber includes a first end coupled to the torch ignitor and a second end coupled and fluidly connected to the manifold. The combustion chamber is configured such that in operation, an ignited fuel and air mixture flows through the combustion chamber, into and through the manifold, and exits through each of the plurality of torch nozzles into the combustor of the gas turbine engine.

The torch ignitor system of the preceding paragraph can optionally include, additionally and/or alternatively, any one or more of the following features, configurations and/or additional components:
The manifold is positioned adjacent and between the high-pressure compressor and the combustor of the gas turbine engine.

The manifold is positioned adjacent and surrounding an outer surface of a combustor liner of the combustor of the gas turbine engine.

The manifold is positioned adjacent a corner of the combustor liner, and wherein the manifold is positioned adjacent a location where fuel nozzles spray fuel into the combustor of the gas turbine engine.

The manifold is positioned axially aft of the fuel nozzles spraying fuel into the combustor of the gas turbine engine.

The torch ignitor is positioned at least partially within the high-pressure case of the gas turbine engine, and wherein the combustion chamber surrounds at least a portion of the torch ignitor.

The torch ignitor includes at least one hot surface ignitor configured to ignite the fuel and air mixture within the combustion chamber.

The at least one hot surface ignitor is a resistance heating element configured to exceed a combustion temperature of the fuel and air mixture to ignite the fuel and air mixture.

The manifold is annular in shape with a circular cross-section such that the manifold is a torus shaped manifold; and the manifold includes tubular walls such that an interior of the manifold is hollow to allow the ignited air and fuel mixture to flow through the manifold.

The manifold is split at a location opposite the location where the second end of the combustion chamber is coupled to the manifold; at least one cap is positioned over an aperture created by the split; and the hollow annular interior of the manifold is blocked from continuous unobstructed flow around the annular interior of the manifold.

Each of the plurality of torch nozzles is positioned adjacent one of the fuel nozzles spraying fuel into the combustor of the gas turbine engine, and wherein the ignited fuel and air mixture exiting each of the plurality of torch nozzles is configured to ignite the fuel exiting each respective fuel nozzle.

Each of the plurality of torch nozzles is positioned adjacent every other one of the fuel nozzles spraying fuel into the combustor of the gas turbine engine, and wherein the ignited fuel and air mixture exiting each of the plurality of torch nozzles is configured to ignite the fuel exiting at least one of the fuel nozzles.

Each of the plurality of torch nozzles is positioned along a centerline of each of the fuel nozzles spraying fuel into the combustor of the gas turbine engine, such that each of the plurality of torch nozzles is incorporated into a respective fuel nozzle to ignite a central portion of the fuel spraying from each fuel nozzle into the combustor of the gas turbine engine.

Each of the plurality of torch nozzles extends from an outer surface of the manifold into the combustor at an oblique angle with respect to a centerline of the fuel nozzles spraying fuel into the combustor of the gas turbine engine.

The combustion chamber further includes quenching apertures positioned within an outer body of the combustion chamber; and the quenching apertures are configured to supply air within the combustion chamber to reduce a temperature of the ignited fuel and air mixture exiting the combustion chamber before entering the manifold of the torch ignitor system.

The combustion chamber includes a plurality of vanes positioned within an outer body of the combustion chamber, and wherein the vanes are configured to allow air to flow through the outer body to cool the combustion chamber.

The combustion chamber and the vanes of the combustion chamber are manufactured using additive manufacturing technology.

The manifold includes a plurality of vanes positioned within an outer wall of the manifold, and wherein the vanes are configured to allow air to flow through the outer wall to cool the manifold.

Two or more torch ignitors are fluidly connected to the manifold to ignite the fuel and air mixture within the combustion chamber and the manifold.

A method of igniting fuel within a combustor of a gas turbine engine including a high-pressure compressor, a high-pressure case, fuel nozzles, and a combustor is disclosed. The method including: igniting, by a torch ignitor of a torch ignitor system, a fuel and air mixture within a combustion chamber of the torch ignitor system, wherein the torch ignitor is coupled to the high-pressure case of the gas turbine engine; flowing the ignited fuel and air mixture through the combustion chamber from a first end of the combustion chamber to a second end of the combustion chamber, wherein the first end is coupled to the torch ignitor and the second end is coupled and fluidly connected to a manifold, and wherein the combustion chamber is positioned within the high-pressure case of the gas turbine engine; flowing the ignited fuel and air mixture from the second end of the combustion chamber into and through the manifold, wherein the manifold is positioned within the high-pressure case of the gas turbine engine; and flowing the ignited fuel and air mixture from the manifold through a plurality of torch nozzles extending from the manifold into the combustor of the gas turbine engine, wherein the ignited fuel and air mixture exits the torch nozzles into the combustor and ignites the fuel sprayed from the fuel nozzles into the combustor of the gas turbine engine.

Claim 1:
A system comprising a high-pressure compressor (<NUM>), a high-pressure case (<NUM>), fuel nozzles (<NUM>), and a combustor (<NUM>) of a gas turbine engine, and a torch ignitor system (<NUM>), the torch ignitor system (<NUM>) comprising:
a torch ignitor (<NUM>) coupled to the high-pressure case (<NUM>) of the gas turbine engine;
a plurality of torch nozzles (<NUM>);
a manifold (<NUM>) positioned within the high-pressure case, with the plurality of torch nozzles (<NUM>) extending from the manifold into the combustor (<NUM>) of the gas turbine engine; and
a combustion chamber (<NUM>) positioned within the high-pressure case, wherein the combustion chamber includes a first end coupled to the torch ignitor and a second end coupled and fluidly connected to the manifold;
wherein the combustion chamber (<NUM>) is configured such that in operation, an ignited fuel and air mixture flows through the combustion chamber, into and through the manifold, and exits through each of the plurality of torch nozzles into the combustor of the gas turbine engine; and
wherein the manifold (<NUM>) includes tubular walls such that an interior of the manifold is hollow to allow the ignited air and fuel mixture to flow through the manifold;
characterised in that the manifold (<NUM>) is annular in shape with a circular cross-section such that the manifold is a torus shaped manifold.