Method and Apparatus of Combustor Dynamics Mitigation

Abstract

A thermo acoustic damper for a combustor includes at least one resonator in flow communication with a flow channel of the combustor. The resonator includes an enclosed volume and at least one baffle plate positioned in the enclosed volume dividing the enclosed volume into at least two volumes. A plurality of feed tubes extend inwardly into at least one of the at least two volumes from the flow channel and are configured to reduce thermo acoustic dynamics of the combustor. A combustor includes an enclosed combustor cap volume and a plurality of fuel nozzles extending through the combustor cap volume. At least one baffle plate is located in the combustor cap volume dividing the combustor cap volume into at least two volumes. A plurality of feed tubes extend inwardly into at least one of the at least two volumes from a flow channel.

1 . A combustor comprising:
 an enclosed combustor cap volume;   a plurality of fuel nozzles extending through the combustor cap volume;   at least one baffle plate disposed in the combustor cap volume dividing the combustor cap volume into at least two volumes; and   a plurality of feed tubes extending inwardly into at least one of the at least two volumes from a flow channel and configured to reduce thermo acoustic dynamics of the combustor.   
     
     
         2 . The combustor of  claim 1  wherein the plurality of feed tubes and at least one of the at least two volumes act as a thermo acoustic damper. 
     
     
         3 . The combustor of  claim 2  wherein a resonator frequency of the thermo acoustic damper counteracts a natural frequency of the combustor. 
     
     
         4 . The combustor of  claim 3  wherein the resonator frequency depends on one or more of a size of the at least one volume, a length of the plurality of feed tubes and a cross-sectional area of the plurality of feed tubes. 
     
     
         5 . The combustor of  claim 1  wherein a position of the at least one baffle plate is determined by a natural frequency of the combustor to be counteracted. 
     
     
         6 . The combustor of  claim 1  wherein the plurality of feed tubes is substantially equally spaced around a perimeter of the combustor. 
     
     
         7 . The combustor of  claim 1  wherein the plurality of feed tubes extend inwardly into each volume of the at least two volumes. 
     
     
         8 . The combustor of  claim 7  wherein each volume of the at least two volumes acts as a thermo acoustic damper to counteract a range of natural frequencies of the combustor. 
     
     
         9 . A thermo acoustic damper for a combustor comprising:
 at least one resonator in flow communication with a flow channel of the combustor, the at least one resonator including:   an enclosed volume;   at least one baffle plate disposed in the enclosed volume dividing the enclosed volume into at least two volumes; and   a plurality of feed tubes extending inwardly into at least one of the at least two volumes from the flow channel and configured to reduce thermo acoustic dynamics of the combustor.   
     
     
         10 . The thermo acoustic damper of  claim 9  wherein a resonator frequency counteracts a natural frequency of the combustor. 
     
     
         11 . The thermo acoustic damper of  claim 10  wherein the resonator frequency depends on one or more of a size of the at least one volume, a length of the plurality of feed tubes and a cross-sectional area of the plurality of feed tubes. 
     
     
         12 . The thermo acoustic damper of  claim 9  wherein a position of the at least one baffle plate is determined by a natural frequency of the combustor to be counteracted. 
     
     
         13 . The thermo acoustic damper of  claim 9  wherein the plurality of feed tubes is substantially equally spaced around a perimeter of the combustor. 
     
     
         14 . The thermo acoustic damper of  claim 9  wherein the plurality of feed tubes extends into each volume of the at least two volumes. 
     
     
         15 . The thermo acoustic damper of  claim 14  wherein each volume of the at least two volumes acts as a resonator to counteract distinct natural frequencies of the combustor. 
     
     
         16 . A method for reducing thermo acoustic combustor dynamics comprising:
 disposing at least one thermo acoustic damper in flow communication with a flow channel of the combustor, the at least one thermo acoustic damper including:   an enclosed volume;   at least one baffle plate disposed in the enclosed volume dividing the enclosed volume into at least two volumes; and   a plurality of feed tubes extending inwardly into at least one of the at least two volumes from the flow channel;   directing a fluid flow through the flow channel and across an open end of at least one feed tube of the plurality of feed tubes; and   exciting a resonance frequency of the at least one thermo acoustic damper thereby reducing the thermo acoustic combustor dynamics.   
     
     
         17 . The method of  claim 16  including counteracting a natural frequency of the combustor via the resonance frequency. 
     
     
         18 . The method of  claim 16  including determining the resonance frequency by adjusting on one or more of a size of the at least one volume, a length of the plurality of feed tubes and a cross-sectional area of the plurality of feed tubes. 
     
     
         19 . The method of  claim 16  including disposing the plurality of feed tubes in each volume of the at least two volumes. 
     
     
         20 . The method of  claim 19  wherein each volume of the at least two volumes acts as a resonator to counteract distinct natural frequencies of the combustor.