The present application provides a spark plug testing tool for a spark plug assembly of a gas turbine engine combustor. The spark plug testing tool may include a dielectric tube attached to the spark plug assembly and a first support bracket to support the spark plug assembly and the dielectric tube therein such that the spark plug assembly remains electrically connected to the gas turbine engine combustor during testing.

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.

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.

An embodiment of a system for measuring fuel ignition within a torch igniter for a combustor in a gas turbine engine includes a housing surrounding and defining a combustion chamber, a first glow plug received through the housing, and control circuitry. An innermost end of the first glow plug extends into the combustion chamber while an outermost end opposite the innermost end extends away from the combustion chamber. The control circuitry is connected to the outermost end of the glow plug and is configured to measure a temperature of the innermost end of the glow plug based on electrical resistance of the glow plug. The control circuitry is further configured to determine an operational parameter of the torch igniter based on the temperature.

An embodiment of a system for measuring fuel ignition within a torch igniter for a combustor in a gas turbine engine includes a housing surrounding and defining a combustion chamber, a first glow plug received through the housing, and control circuitry. An innermost end of the first glow plug extends into the combustion chamber while an outermost end opposite the innermost end extends away from the combustion chamber. The control circuitry is connected to the outermost end of the glow plug and is configured to measure a temperature of the innermost end of the glow plug based on electrical resistance of the glow plug. The control circuitry is further configured to determine an operational parameter of the torch igniter based on the temperature.

An ignition and combustion assist system and method comprising a plasma igniter and electronic driver unit for use with gas turbine engines operating under low air densities, reduced voltage conditions and overall pressure ratios of 3:1 to 7:1. The plasma igniter has an inner chamber housing a centrally positioned and electrically isolated electrode attached to an electrical lead, driver unit, and AC or DC power supply. The electrode features a corner positioned near an outlet end of the igniter, where a plasma arc ignites a fuel-air mixture creating a flame extending into a primary burn region of a combustor of the gas turbine. The driver unit is in two embodiments and configured with low-cost microsecond voltage wave time periods or energy-efficient nano-second pulses. The method uses the plasma igniter and the electronic driver units described herein separately with other components or together.

An ignition and combustion assist system and method comprising a plasma igniter and electronic driver unit for use with gas turbine engines operating under low air densities, reduced voltage conditions and overall pressure ratios of 3:1 to 7:1. The plasma igniter has an inner chamber housing a centrally positioned and electrically isolated electrode attached to an electrical lead, driver unit, and AC or DC power supply. The electrode features a corner positioned near an outlet end of the igniter, where a plasma arc ignites a fuel-air mixture creating a flame extending into a primary burn region of a combustor of the gas turbine. The driver unit is in two embodiments and configured with low-cost microsecond voltage wave time periods or energy-efficient nano-second pulses. The method uses the plasma igniter and the electronic driver units described herein separately with other components or together.

The electrical circuit of power supply includes a series of discharge gaps, storage capacitors, and charging resistors. The work of multispark reactor based on the parallel breakdown of discharge gaps in the mode of self-breakdown. Simultaneous triggering of all gaps is achieved using self-breakdown on the rising edge of voltage, particularly when using the power frequency AC voltage.

The electrical circuit of power supply includes a series of discharge gaps, storage capacitors, and charging resistors. The work of multispark reactor based on the parallel breakdown of discharge gaps in the mode of self-breakdown. Simultaneous triggering of all gaps is achieved using self-breakdown on the rising edge of voltage, particularly when using the power frequency AC voltage.

An embodiment of a combustor for a gas turbine engine includes a combustor case, a combustor liner disposed within the combustor case, a fuel nozzle at an upstream end of the combustor liner, a torch igniter within the combustor case, and a removable fuel injector. The torch igniter includes a combustion chamber, a cap configured to receive a removable fuel injector and a surface igniter, a tip, an annular igniter wall extending from the cap to the tip and defining a radial extent of the combustion chamber, a structural wall coaxial with and surrounding the igniter wall, and an outlet passage within the tip which fluidly connects the combustion chamber to the combustor. The removable fuel injector extends through a fuel injector opening of the combustor case. The diameter of the fuel injector opening is wider than a fuel injector diameter of the removable fuel injector.