66 results about "Combustion kinetics" patented technology

Tuning processes implemented by an auto-tune controller are provided for measuring and adjusting the combustion dynamics and the emission composition of a gas turbine (GT) engine via a tuning process. Initially, the tuning process includes monitoring parameters, such as combustion dynamics and emission composition. Upon determining that one or more of the monitored parameters exceed a critical value, these “out-of-tune” parameters are compared to a scanning order table. Upon comparison, the first out-of-tune parameter that is matched within the scanning order table is addressed. The first out-of-tune parameter is then plotted as overlaid slopes on respective graphs, where the graph represents a fuel-flow split. Typically, the slopes are plotted as a particular out-of-tune parameter against a particular fuel-flow split. The slopes for each graph are considered together by taking into account the combined impact on each out-of-tune parameter when a fuel-flow split is selected for adjustment.

A method and system (14) for monitoring a health of a combustion dynamics sensing system (10) includes monitoring respective dynamic conditions of at least two combustor cans (16) of a can annular combustor (12) of a gas turbine engine with respective dynamic condition sensors (20) associated with each of the cans. The method also includes establishing a baseline relationship between the respective dynamic conditions and then identifying a variance from the baseline relationship indicative of a degraded signal quality provided by a dynamic condition sensor associated with at least one of the cans.

Methods and systems are provided for inducing combustion dynamics within turbine engines to remove combustion deposits within the turbine engine during operation of the turbine engine.

A combustor includes an end cap that extends radially across at least a portion of the combustor. The end cap includes an upstream surface axially separated from a downstream surface. A plurality of tubes extend from the upstream surface through the downstream surface of the end cap to provide fluid communication through the end cap. Each tube in a first set of the plurality of tubes has an inlet proximate to the upstream surface and an outlet downstream from the downstream surface. Each outlet has a first portion that extends a different axial distance from the inlet than a second portion.

A method for monitoring and diagnosing the combustion dynamics of a gas turbine engine system includes mounting at least one sensor on an external surface of at least one combustor can, receiving a signal from the sensor mounted to the combustor can, validating an accuracy of the signal from the sensors, determining the combustion dynamics of the can based on the received signals, and generating an indication when a combustion dynamic threshold has been exceeded.

Thermoacoustic sensors, such as dynamic pressure sensors, in the combustor measure vibratory responses of the combustor. An integrated monitoring and control system controller correlates sensor readings with combustion thermoacoustic properties in order to identify combustion anomalies by wavelet or Fourier analysis techniques; determine bulk temperature characteristics within the combustor with dominant mode frequency analysis techniques; and optionally determines absolute active path temperatures within the combustor with acoustic pyrometry transmission and time-of-flight analysis techniques. In some embodiments all of the monitoring functions are performed with a commonly shared array of thermoacoustic sensors that function as both combustion dynamics thermoacoustic vibration/wave receivers and acoustic transmitters. The monitored combustion properties are used for controlling gas turbine combustion.

A system and method for reducing combustion dynamics includes first and second combustors arranged about an axis, and each combustor includes a plurality of tubes that extend axially through at least a portion of the combustor and a combustion chamber downstream from the plurality of tubes. A fuel injector extends through each tube to provide fluid communication into each tube at a fourth axial distance from the combustion chamber. The fourth axial distance in the first combustor is different than the fourth axial distance in the second combustor.

A system for reducing combustion dynamics and NO_x in a combustor includes a tube bundle that extends radially across at least a portion of the combustor, wherein the tube bundle comprises an upstream surface axially separated from a downstream surface. A shroud circumferentially surrounds the upstream and downstream surfaces. A plurality of tubes extends through the tube bundle from the upstream surface through the downstream surface, wherein the downstream surface is stepped to produce tubes having different lengths through the tube bundle. A method for reducing combustion dynamics and NO_x in a combustor includes flowing a working fluid through a plurality of tubes radially arranged between an upstream surface and a downstream surface of an end cap that extends radially across at least a portion of the combustor, wherein the downstream surface is stepped.

A method for monitoring combustion dynamics of a can annular combustor (12) of a gas turbine engine includes monitoring respective dynamic operating conditions of cans (16) of the can annular combustor with respective dynamic operating condition sensors (20) associated with each of the cans. The method also includes grouping the cans into two or more groups according to their respective dynamic operating conditions and identifying a sensor providing an anomalous dynamic operating condition reading for at least one of the cans. The method further includes determining a need to service the identified sensor according to the associated can's group membership.

A method of managing transient events regularly seen during gas turbine operation that may cause undesirable operation and hardware damage. During certain transient operations, a lag may be seen between reference exhaust temperature and actual turbine exhaust temperature. This lag can result in an under-fired condition within the combustion system of variable magnitude and duration. Either fuel split schedules or a control algorithm can be positioned during these transients to prevent combustion dynamics or loss of flame. Combustion dynamics are known to cause damage that may require hardware replacement. Once the transient has completed, normal control operation is resumed.

A method for controlling combustion dynamics is provided. The method includes providing a flow of partially premixed, premixed, or lean premixed fuel-air into a combustion chamber. The method also includes monitoring the combustion system for combustion dynamics. The method further includes actuating a system to control and abate combustion dynamics.

A dry low NOx (DLN) fuel nozzle of a fuel system is provided and includes one or more downstream orifices formed to define a first fluid path along which fluid is directed to flow, an upstream orifice, located upstream from the one or more downstream orifices, formed to define a second fluid path along which the fluid is directed to flow and connecting passages disposed to fluidly couple the first and second fluid paths of the downstream and upstream orifices, respectively, to one another. At least one of a radial size and an axial location of the upstream orifice is set to cooperatively detune an acoustic impedance of the fuel system.

A combustion liner cap assembly includes a cylindrical outer sleeve supporting internal structure therein and a plurality of fuel nozzle openings formed through the internal structure. A first set of circumferentially spaced cooling holes is formed through the cylindrical outer sleeve, and a second set of circumferentially spaced cooling holes is formed through the cylindrical outer sleeve. The second set of cooling holes is axially spaced from the first set of cooling holes. The resulting construction serves to decrease combustion dynamics in a simplified manner that is retrofittable to current designs and reversible without impacting the original configuration. The reduction in combustion dynamics improves hardware life, which leads to reduced repair and replacement costs.

A system for reducing combustion dynamics in a combustor includes an end cap having an upstream surface axially separated from a downstream surface, and tube bundles extend through the end cap. A diluent supply in fluid communication with the end cap provides diluent flow to the end cap. Diluent distributors circumferentially arranged inside at least one tube bundle extend downstream from the downstream surface and provide fluid communication for the diluent flow through the end cap. A method for reducing combustion dynamics in a combustor includes flowing fuel through tube bundles that extend axially through an end cap, flowing a diluent through diluent distributors into a combustion chamber, wherein the diluent distributors are circumferentially arranged inside at least one tube bundle and each diluent distributor extends downstream from the end cap, and forming a diluent barrier in the combustion chamber between at least one pair of adjacent tube bundles.

Methods and systems for analyzing combustion dynamics of a combustor system in the time domain are provided. The combustor system includes an inlet pipe coupled in flow communication with a combustion chamber. The method includes determining a characteristic equation of a wave traveling in the inlet pipe, determining an acoustic pressure oscillation in the combustion chamber, and determining a pressure fluctuation in the inlet pipe using the characteristic equation and the determined acoustic pressure oscillation.