Abstract: An example system and corresponding method can include a combustion chamber of jet engine, a radio-frequency power source, and a resonator. The combustion chamber can include a liner defining a combustion zone, and include a fuel inlet configured to introduce fuel into the combustion zone. The resonator can have a resonant wavelength and include: a first conductor, a second conductor, a dielectric, and an electrode coupled to the first conductor. The resonator can be configured such that, when the resonator is excited by the radio-frequency power source with a signal having a wavelength proximate to an odd-integer multiple of one-quarter (¼) of the resonant wavelength, the resonator provides a plasma corona in the combustion zone. The controller can be configured to cause the radio-frequency power source to excite the resonator with the signal so as to provide the plasma corona.

Abstract: An apparatus for igniting a combustible mixture. In one example, the apparatus can include a coaxial cavity resonator assembly in a combustion environment. The apparatus can also include an operational feedback system and a controller. The operational feedback system can measure at least one of a voltage value and a current value of the coaxial cavity resonator assembly in the combustion environment. The controller can be configured to determine a condition of the coaxial cavity resonator assembly and modulate operation of the coaxial cavity resonator assembly based at least in part on the determined condition.

Abstract: An apparatus for igniting a combustible mixture. In one example, the apparatus can include a coaxial cavity resonator assembly in a combustion environment. The apparatus can also include an operational feedback system and a controller. The operational feedback system can measure at least one of a voltage value and a current value of the coaxial cavity resonator assembly in the combustion environment. The controller can be configured to determine a condition of the coaxial cavity resonator assembly and modulate operation of the coaxial cavity resonator assembly based at least in part on the determined condition.

Abstract: An apparatus comprises a coaxial cavity resonator; a radio frequency power source coupled to the coaxial cavity resonator; a direct current power source coupled to the coaxial cavity resonator; a combustion process feedback module configured to sense a condition in a combustion environment by measuring a characteristic of the coaxial cavity resonator; and a controller configured to modulate operation of the coaxial cavity resonator based at least in part on combustion process feedback information from the combustion process feedback module.

Abstract: An apparatus comprises a coaxial cavity resonator; a radio frequency power source coupled to the coaxial cavity resonator; a direct current power source coupled to the coaxial cavity resonator; a combustion process feedback module configured to sense a condition in a combustion environment by measuring a characteristic of the coaxial cavity resonator; and a controller configured to modulate operation of the coaxial cavity resonator based at least in part on combustion process feedback information from the combustion process feedback module.

Abstract: An example system and corresponding method can include a combustion chamber of jet engine, a radio-frequency power source, and a resonator. The combustion chamber can include a liner defining a combustion zone, and include a fuel inlet configured to introduce fuel into the combustion zone. The resonator can have a resonant wavelength and include: a first conductor, a second conductor, a dielectric, and an electrode coupled to the first conductor. The resonator can be configured such that, when the resonator is excited by the radio-frequency power source with a signal having a wavelength proximate to an odd-integer multiple of one-quarter (¼) of the resonant wavelength, the resonator provides a plasma corona in the combustion zone. The controller can be configured to cause the radio-frequency power source to excite the resonator with the signal so as to provide the plasma corona.

Abstract: An example system can include a combustor of a jet turbine engine, a radio-frequency power source, a plasma-distributing structure, and a resonator having a first concentrator. The combustor can include one or more fins protruding into a combustion zone and can be configured to guide combustion of fuel along a flame path defined by the fin(s). The resonator can be configured to provide a plasma corona when excited by the power source. The plasma-distributing structure can be arranged within the combustor and proximate to the plasma corona, and can include a second concentrator. When the resonator is excited, the plasma corona can be provided proximate to the first concentrator. Further, when the plasma corona is provided proximate to the first concentrator and the plasma-distributing structure is at a predetermined voltage, an additional plasma corona can be established proximate to the second concentrator and at least partly within the flame path.

Abstract: A system includes an afterburner including an afterburner duct that defines an afterburner channel. The afterburner is configured to receive input gas from a jet engine turbine into the channel and to output an exhaust gas resulting from combustion of fuel. The system includes a plurality of resonators electromagnetically coupled to at least one radio-frequency power source. Each resonator has a resonant wavelength, first and second conductors, and a dielectric between those conductors. Each resonator is configured such that, when that resonator is excited by the power source with a signal having a wavelength proximate to an odd-integer multiple of one-quarter of the resonant wavelength of that resonator, that resonator provides within the afterburner at least one of electromagnetic waves or a plasma corona proximate to that resonator. A first resonator further includes a fuel conduit having a fuel outlet configured to output fuel for mixing with the input gas.

Abstract: An example system can include a combustion chamber of a jet engine, one or more radio-frequency power sources, a plurality of resonators, and a fuel conduit. The plurality of resonators can be electromagnetically coupled to the one or more radio-frequency power sources and each have a respective resonant wavelength. Further, each resonator can include (i) a respective first conductor, (ii) a respective second conductor, and (iii) a respective dielectric between the first conductor and the second conductor, and can be configured to provide at least one of a plasma corona or electromagnetic waves. The fuel conduit can be configured to couple to a fuel source and have a fuel outlet for expelling fuel into a combustion zone of the combustion chamber. A portion of the fuel conduit is disposed within the first conductor of a given resonator of the plurality of resonators.

Abstract: An example system can include a radio-frequency power source and a resonator. The resonator can be configured to be electromagnetically coupled to the radio-frequency power source and can have a resonant wavelength. The resonator can include: a first conductor, a second conductor, and a dielectric between the first conductor and the second conductor. The resonator can also be configured such that, when the resonator is excited by the radio-frequency power source with a signal having a wavelength proximate to an odd-integer multiple of one-quarter of the resonant wavelength, the resonator provides at least one of a plasma corona or electromagnetic waves. The system can also include a fuel conduit configured to couple to a fuel source and having one or more outlets for expelling fuel, where at least a portion of the fuel conduit is arranged proximate to the dielectric.

Abstract: An example system can include a combustion chamber of a power-generation gas turbine, a radio-frequency power source, a direct-current power source, a resonator, and a fuel conduit. The resonator can be electromagnetically coupled to the radio-frequency power source and have a resonant wavelength. Further, the resonator can include (i) a first conductor, (ii), a second conductor, and (iii) a dielectric between the first conductor and the second conductor. The resonator can be configured to provide at least one of a plasma corona or electromagnetic waves. The fuel conduit can be configured to couple to a fuel source and have a fuel outlet for expelling fuel into a combustion zone of the combustion chamber. A portion of the fuel conduit is disposed within the first conductor.

Abstract: An example system and corresponding method includes a jet engine combustor and a resonator. The combustor includes (i) a combustion zone, (ii) one or more fuel inlets for introducing fuel into the combustion zone for combustion, and (iii) one or more fins protruding into the combustion zone and configured to guide combustion of the fuel along a flame path. The resonator can have a resonant wavelength and can provide a plasma corona in the combustion zone when excited with a signal having a wavelength proximate to an odd-integer multiple of one-quarter (¼) of the resonant wavelength. A radio-frequency power source can excite the resonator with the signal so as to provide the plasma corona in the combustion zone and cause combustion of the fuel along the flame path.

Abstract: A system includes a radio-frequency power source, a resonator, and an afterburner including a duct that defines a channel. The afterburner receives input gas from a turbine of a jet engine into the channel and outputs an exhaust gas resulting from combustion of fuel within the channel. The resonator, having a resonant wavelength, is electromagnetically coupled to the power source. The resonator includes first and second conductors, a dielectric between the conductors, an electrode coupled to the first conductor and disposed within the afterburner, and a fuel conduit having a fuel outlet that is configured to output fuel for mixing with the input gas from the turbine of the jet engine. The resonator, when excited by the power source with a signal having a wavelength proximate to an odd-integer multiple of one-quarter of the resonant wavelength, provides electromagnetic waves and/or a plasma corona proximate to a concentrator of the electrode.

Abstract: Example implementations relate to jet engines that include resonator-based diagnostics. An example implementation includes a jet engine. The jet engine includes a combustion chamber configured to house a combustion event of a fuel mixture. The jet engine also includes a resonator having a characteristic impedance and a resonant wavelength. The resonator includes a first conductor and a second conductor separated from one another by an interstitial space that is exposed to an environment of the combustion chamber. Further, the jet engine includes a controller communicatively coupled to the resonator and configured to perform operations. The operations include determining a characteristic of the resonator selected from the group consisting of the characteristic impedance and the resonant wavelength. The operations also include, based on the determined characteristic, determining a parameter of the combustion chamber.

Abstract: An example system can include a combustion chamber of a power-generation gas turbine, one or more radio-frequency power sources, a plurality of resonators, and a fuel conduit. The plurality of resonators can be electromagnetically coupled to the one or more radio-frequency power sources and each have a respective resonant wavelength. Further, each resonator can include (i) a respective first conductor, (ii) a respective second conductor, and (iii) a respective dielectric between the first conductor and the second conductor, and can be configured to provide at least one of a plasma corona or electromagnetic waves. The fuel conduit can be configured to couple to a fuel source and have a fuel outlet for expelling fuel into a combustion zone of the combustion chamber. A portion of the fuel conduit is disposed within the first conductor of a given resonator of the plurality of resonators.

Abstract: An example system can include a combustion chamber of a jet engine, a radio-frequency power source, a resonator, and a fuel conduit. The resonator can be electromagnetically coupled to the radio-frequency power source and have a resonant wavelength. Further, the resonator can include (i) a first conductor, (ii), a second conductor, and (iii) a dielectric between the first conductor and the second conductor. The resonator can be configured such that, when the resonator is excited by the radio-frequency power source with a signal having a wavelength proximate to an odd-integer multiple of one-quarter of the resonant wavelength, the resonator provides at least one of a plasma corona or electromagnetic waves. The fuel conduit can be configured to couple to a fuel source and have a fuel outlet for expelling fuel into a combustion zone of the combustion chamber. A portion of the fuel conduit is arranged proximate to the dielectric.

Abstract: An example system and corresponding method can include a combustion chamber of jet engine, a radio-frequency power source, and a resonator. The combustion chamber can include a liner defining a combustion zone, and include a fuel inlet configured to introduce fuel into the combustion zone. The resonator can have a resonant wavelength and include: a first conductor, a second conductor, a dielectric, and an electrode coupled to the first conductor. The resonator can be configured such that, when the resonator is excited by the radio-frequency power source with a signal having a wavelength proximate to an odd-integer multiple of one-quarter (¼) of the resonant wavelength, the resonator provides a plasma corona in the combustion zone. The controller can be configured to cause the radio-frequency power source to excite the resonator with the signal so as to provide the plasma corona.

Abstract: An example system can include a radio-frequency power source, a resonator, and a plasma-distributing structure. The resonator can include an electrode having a first concentrator. The resonator can be configured to provide a plasma corona when excited by the power source with a signal having a wavelength proximate to an odd-integer multiple of one-quarter of a resonant wavelength of the resonator. The plasma-distributing structure can be arranged proximate to the plasma corona provided by the resonator and include a second concentrator. When the power source excites the resonator with the signal, an electric field can be concentrated at the first concentrator and the plasma corona can be provided proximate to the first concentrator. Further, when the plasma corona is provided proximate to the first concentrator and the plasma-distributing structure is at a predetermined voltage, an additional plasma corona can be established proximate to the second concentrator.

Abstract: An example system and corresponding method includes a jet engine combustor and a plurality of resonators. The combustor includes (i) a combustion zone, (ii) one or more fuel inlets for introducing fuel into the combustion zone for combustion, and (iii) one or more fins protruding into the combustion zone and configured to guide combustion of the fuel along a flame path. The resonators can each have a respective resonant wavelength and can each provide a respective plasma corona in the combustion zone when excited with a respective signal having a wavelength proximate to an odd-integer multiple of one-quarter (¼) of the respective resonant wavelength. A radio-frequency power source can excite the resonators with the respective signals so as to provide the respective plasma coronas in the combustion zone and cause combustion of the fuel along the flame path.

Abstract: Example implementations relate to electromagnetic wave modification of fuel in a jet engine. An example implementation includes a jet engine. The jet engine includes a combustion chamber, a radio-frequency power source, and a fuel conduit configured to provide a fuel to the combustion chamber. In addition, the jet engine includes a resonator configured to electromagnetically couple to the radio-frequency power source and having a resonant wavelength. The resonator includes a first conductor, a second conductor, and a dielectric between the first conductor and the second conductor. The resonator is configured such that, when the resonator is excited by the radio-frequency power source with a signal having a wavelength proximate to an odd-integer multiple of one-quarter (¼) of the resonant wavelength, the resonator radiates electromagnetic waves usable to modify (i) the fuel within the fuel conduit or (ii) a fuel mixture, which includes the fuel, within the combustion chamber.