Methods and systems to detect flameholding in turbine assemblies

A method of operating a turbine engine at reduced emissions and reduced audible noise, the method comprising:

• supplying a fuel mixture having a second hydrogen gas concentration to at least one combustor of the turbine engine, wherein the second hydrogen gas concentration defines a broadened flameholding margin window of the turbine engine, the broadened flameholding margin window resulting in the reduced emissions and reduced audible noise of the turbine engine;
• measuring, via a sensor, dynamic pressure data within at least one combustor of the turbine engine;
• converting, via a processor, the dynamic pressure data to frequency-domain spectral energy amplitudes associated with the dynamic pressure data;
• comparing the spectral energy amplitudes against a dynamic amplitude threshold value stored in a memory to determine whether the spectral energy amplitudes exceed the dynamic amplitude threshold value, wherein the spectral energy amplitudes exceeding the dynamic amplitude threshold value indicate a flameholding occurrence;
• and
• mitigating flameholding conditions of the at least one combustor by adjusting the hydrogen gas concentration of the fuel mixture supplied to the at least one combustor from the second hydrogen gas concentration to a first hydrogen gas concentration, wherein the second hydrogen gas concentration is higher than the first hydrogen gas concentration, wherein the first hydrogen gas concentration defines a standard operating window.

A system to facilitate operating at least one combustor of a turbine engine within flameholding margins, the system comprising:

• a fuel injection system coupled in flow communication with a blended fuel supply for supplying a fuel mixture into at least one fuel injector within the at least one combustor of the turbine engine, the fuel mixture having a hydrogen gas concentration adjustable from a first hydrogen gas concentration to a second hydrogen gas concentration, the second hydrogen gas concentration being higher than the first hydrogen gas concentration;
• and
• a detection system including a processor and a plurality of dynamic pressure sensors, the processor programmed to:
• supply the fuel mixture with the second hydrogen gas concentration to the turbine engine, wherein the second hydrogen gas concentration defines a broadened flameholding margin window of the turbine engine, wherein the broadened flameholding margin window enables the turbine engine to operate at higher mechanical power output, reduced emissions, and reduced audible noise relative to the turbine engine operating at the first hydrogen gas concentration;
• receive, from one or more of the plurality of dynamic pressure sensors, dynamic pressure data measured within the at least one combustor of the turbine engine;
• convert the dynamic pressure data to frequency-domain spectral energy amplitudes associated with the dynamic pressure data;
• compare the spectral energy amplitudes against a dynamic amplitude threshold to determine whether the spectral energy amplitudes exceed the dynamic amplitude threshold, wherein spectral energy amplitudes exceeding the dynamic amplitude threshold indicate a flameholding occurrence;
• and
• decrease the hydrogen gas concentration of the fuel mixture from the second hydrogen gas concentration to the first hydrogen gas concentration, wherein the first hydrogen gas concentration defines a standard operating window that has a reduced likelihood of flameholding as compared to the broadened flameholding margin window.