Trapped vortex combustor and method for operating the same

Abstract

Various embodiments include a trapped vortex combustor and a method for operating trapped vortex combustor. In one embodiment, the trapped vortex combustor comprises a trapped vortex combustion zone and at least one secondary combustion zone disposed downstream of the trapped vortex combustion zone. The trapped vortex combustion zone is operable to receive and combust a first fuel and a first air and produce a first combustion product flowing toroidally therein. The at least one secondary combustion zone is operable to receive and combust the first combustion product and at least one second injection consisting of fuel and/or air and produce at least one second combustion product therein. The combustor may reduce the residence time of the highest temperature combustion products and achieve the lower NOx emission.

What is claimed is: 
     
         1 . A trapped vortex combustor of a gas turbine engine, comprising:
 a trapped vortex combustion zone operable to receive and combust a first injection comprising a first fuel and a first air and produce a first combustion product flowing toroidally therein; and   at least one secondary combustion zone disposed downstream of the trapped vortex combustion zone, and operable to receive and combust the first combustion product and at least one second injection comprising at least one of a second fuel or a second air and produce at least one second combustion product therein,   wherein the trapped vortex combustion zone is disposed radially inside of the at least one secondary combustion zone.   
     
     
         2 . The trapped vortex combustor of  claim 1 , further comprising a combustor exit, wherein the at least one secondary combustion zone is located nearer to the combustor exit than the trapped vortex combustion zone. 
     
     
         3 . The trapped vortex combustor of  claim 1 , wherein the trapped vortex combustion zone is disposed wholly radially inside of the at least one secondary combustion zone. 
     
     
         4 . The trapped vortex combustor of  claim 1 , wherein the trapped vortex combustor comprises an annular combustor, and the trapped vortex combustion zone is configured as substantially arcuate in a longitudinal cross-section. 
     
     
         5 . The trapped vortex combustor of  claim 1 , wherein the trapped vortex combustor utilizes one or more pilot fuel nozzles for introducing the first fuel into the trapped vortex combustion zone to mix with the first air. 
     
     
         6 . The trapped vortex combustor of  claim 5 , wherein the first air and the first fuel enter the trapped vortex combustion zone in directions opposite of each other along an axis of the gas turbine engine. 
     
     
         7 . The trapped vortex combustor of  claim 5 , wherein the first air and the first fuel enter the trapped vortex combustion zone in a direction parallel with each other along an axis of the gas turbine engine. 
     
     
         8 . The trapped vortex combustor of  claim 1 , wherein the trapped vortex combustion zone is configured as a trapped vortex combustion cavity, and the first air is directed into the trapped vortex combustor along a periphery of the trapped vortex combustion cavity. 
     
     
         9 . The trapped vortex combustor of  claim 8 , wherein at least one of the first air or the first combustion product in the trapped vortex combustion cavity is operable to flow in a clockwise direction. 
     
     
         10 . The trapped vortex combustor of  claim 8 , wherein at least one of the first air or the first combustion product in the trapped vortex combustion cavity is operable to flow in a counterclockwise direction. 
     
     
         11 . A trapped vortex combustor of a gas turbine engine, comprising:
 a trapped vortex combustion zone operable to receive and combust a first injection comprising a first fuel and a first air and produce a first combustion product flowing therein; and   at least one secondary combustion zone disposed downstream of the trapped vortex combustion zone, and operable to receive and combust the first combustion product and at least one second injection of a second fuel radially into the at least one secondary combustion zone and produce at least one second combustion product therein,   wherein the trapped vortex combustion zone is disposed radially inside of the at least one secondary combustion zone.   
     
     
         12 . The trapped vortex combustor of  claim 11 , further comprising a combustor exit, wherein the at least one secondary combustion zone is located nearer to the combustor exit than the trapped vortex combustion zone. 
     
     
         13 . The trapped vortex combustor of  claim 11 , wherein the trapped vortex combustion zone is disposed wholly radially inside of the at least one secondary combustion zone. 
     
     
         14 . The trapped vortex combustor of  claim 11 , wherein the trapped vortex combustor comprises an annular combustor, and the trapped vortex combustion zone is configured as substantially arcuate in a longitudinal cross-section. 
     
     
         15 . The trapped vortex combustor of  claim 11 , wherein the trapped vortex combustor utilizes one or more pilot fuel nozzles for introducing the first fuel into the trapped vortex combustion zone to mix with the first air. 
     
     
         16 . The trapped vortex combustor of  claim 15 , wherein the first air and the first fuel enter the trapped vortex combustion zone in directions opposite of each other along an axis of the gas turbine engine. 
     
     
         17 . The trapped vortex combustor of  claim 15 , wherein the first air and the first fuel enter the trapped vortex combustion zone in a direction parallel with each other along an axis of the gas turbine engine. 
     
     
         18 . The trapped vortex combustor of  claim 11 , wherein the trapped vortex combustion zone is configured as a trapped vortex combustion cavity, and the first air is directed into the trapped vortex combustor along a periphery of the trapped vortex combustion cavity. 
     
     
         19 . The trapped vortex combustor of  claim 18 , wherein at least one of the first air or the first combustion product in the trapped vortex combustion cavity is operable to flow in a clockwise direction. 
     
     
         20 . The trapped vortex combustor of  claim 18 , wherein at least one of the first air or the first combustion product in the trapped vortex combustion cavity is operable to flow in a counterclockwise direction.