A resonant sound absorbing device of a gas turbine combustor includes a plurality of resonance chambers independently disposed side by side in an axial direction of the gas turbine combustor so as to communicate with a gas passage of the gas turbine combustor via acoustic holes. The plurality of resonance chambers include n related resonance chambers each satisfying: $\begin{array}{cc}0.9\times {.Math.}_{i=1}^n\frac{F_i}{n}\le F_i\le 1.1\times {.Math.}_{i=1}^n\frac{F_i}{n}& \left(A\right)\end{array}$
where n is an integer of 2 or more, and Fi is a peak frequency corresponding to a maximum sound absorbing ratio of the ith related resonance chamber of the n related resonance chambers.

An exhaust system includes an exhaust manifold structured to be fluidly coupled to an engine. A turbocharger including a turbine housing is fluidly coupled to the exhaust manifold. An exhaust pulse converter includes a first portion integral to the exhaust manifold and a second portion integral to the turbine housing. The exhaust pulse converter is structured to reduce engine pumping losses by reducing cross-talk of exhaust blowdown events from the engine.

The present disclosure is directed to a method of operating a combustion system to attenuate combustion dynamics. The method includes flowing, via a compressor section, an overall supply of air to the combustion system; flowing, via a fuel supply system, an overall flow of fuel to the combustion system; flowing, to a first fuel nozzle of the combustion system, a first supply of fuel defining a richer burning fuel-air mixture at the first fuel nozzle; flowing, to a second fuel nozzle of the combustion system, a second supply of fuel defining a leaner burning fuel-air mixture at the second fuel nozzle; and igniting the richer burning fuel-air mixture and the leaner burning fuel-air mixture to produce an overall fuel-air ratio at a combustion chamber of the combustion system.

A rotary machine includes at least one burner including a front panel having a front side and an opposing back side. The acoustic damper includes at least one wall, at least one cooling air inlet, at least one outlet, and at least one baffle. The wall extends from the back side of the front panel and defines a dampening chamber. The cooling air inlet is defined within the back side of the front panel and is configured to channel a flow of cooling air into the dampening chamber. The outlet is defined within the back side of the front panel and is configured to channel the flow of cooling air out of the dampening chamber. The baffle extends from the back side of the front panel and is configured to reduce a velocity of the flow of cooling air within the dampening chamber.

A noise attenuation panel for a structure within a propulsion system includes a first plurality of unit cells; and a second plurality of unit cells, the second plurality of unit cells merged within the first plurality of unit cells, the first plurality of unit cells including a first periodic structure having a first unit cell, a second unit cell, a third unit cell and a fourth unit cell, each of the first unit cell, the second unit cell, the third unit cell and the fourth unit cell including a central body interconnected via a plurality of lateral tubes extending from the central body, the first periodic structure forming a first lateral layer of unit cells.

A Brayton cycle engine including a longitudinal wall extended along a lengthwise direction. The longitudinal wall defines a gas flowpath of the engine. An inner wall assembly is extended from the longitudinal wall into the gas flowpath. The inner wall assembly defines a detonation combustion region in the gas flowpath upstream of the inner wall assembly.

A method, control unit and rotating machine for determining a fuel split setting value for adjusting a fuel split setting for a combustion device, the fuel split setting defining a relation between main fuel and pilot fuel. The method includes: retrieving a first information item correlated to heating value of supplied main fuel; retrieving a second information item correlated to combustor operating condition; retrieving at least one third information item representing stability of combustion; selecting a predefined pair of minimum and maximum boundary curves for the fuel split setting from a plurality of predefined pairs based on the first and second information items, the minimum and maximum boundary curves defining a band of fuel split settings permitted for a range of second information item values; determining the fuel split setting value within the selected pair of minimum and maximum boundary curves based on the third information item.

A method for controlling a gas turbine, having a measurement step, a prediction step which is carried out after the measurement step, and a control step which is carried out after the prediction step. In the measurement step, a state variable of a combustion within a gas turbine is measured. In the prediction step, a future combustion dynamic is predicted using the measured state variable. In the control step, a control signal is output using the prediction of the future combustion dynamic.

A gas turbine engine may include a combustion section having a fuel nozzle, a swirler, and a ferrule configured to mount and center the fuel nozzle with the swirler. The combustion section may further include a damper on a cold side of the combustion section. The damper may have an acoustic cavity, a damper neck, and a cavity feed hole. The damper may operate as Helmholtz cavity to absorb a hydrodynamic or acoustic instability present in a region within the swirler.

The gas turbine comprises a compressor, a combustor, and a turbine. The method comprises: compressing air with the compressor and feeding compressed air continuously to the combustor, feeding fuel to the combustor, continuously firing the mixture of fuel and gas in the combustor, feeding combustion gases from the combustor to the turbine, and supplying at least a portion of the total amount of fuel that is supplied to the combustor intermittently.