Low net-swirl configurations for gas turbine engine combustors

Abstract

The present disclosure relates to gas turbine engines, and in particular to combustor swirlers and swirler configurations. In one embodiment, a swirler includes an inner passage for receiving a fuel injector and a plurality of outer passages concentrically arranged around the inner passage. The plurality of outer passages include an outer vane assembly including a plurality of vane elements arranged at a first angle and a first middle vane assembly include a plurality of vane elements arranged at a second angle, wherein the outer vane assembly is concentrically arranged around the first middle vane assembly, and wherein the outer vane assembly and first middle vane assembly are configured to produce a low net-swirl to control the penetration depth and improve premixing of a fuel air mixture for the fuel injector. According to another embodiment, the swirler includes a second middle vane assembly include a plurality of vane elements arranged at a third angle.

What is claimed is: 
     
         1 . A swirler for a combustor of a gas turbine engine, the swirler comprising:
 an inner passage for receiving a fuel injector;   a plurality of outer passages concentrically arranged around the inner passage, wherein the plurality of outer passages include
 an outer vane assembly including a plurality of vane elements arranged at a first angle; and 
 a first middle vane assembly include a plurality of vane elements arranged at a second angle, 
   wherein the outer vane assembly is concentrically arranged around the first middle vane assembly, and wherein the outer vane assembly and first middle vane assembly are configured to produce a low net-swirl to control the penetration depth of a fuel air mixture for the fuel injector.   
     
     
         2 . The swirler of  claim 1 , wherein the swirler is configured to generate an air and fuel mixture downstream of a combustor pilot flow and improve premixing of the fuel air mixture. 
     
     
         3 . The swirler of  claim 1 , wherein vanes of the outer vane assembly are angled within the range of +45 to +60 degrees. 
     
     
         4 . The swirler of  claim 1 , wherein vanes of the outer vane assembly are arranged and configured to handle within 50 to 70 percent of the airflow received by the swirler. 
     
     
         5 . The swirler of  claim 1 , wherein vanes of the first middle vane assembly are angled within the range of 0 to −25 degrees. 
     
     
         6 . The swirler of  claim 1 , wherein vanes of the first middle vane assembly are arranged and configured to handle within 20 to 40 percent of the airflow received by the swirler. 
     
     
         7 . The swirler of  claim 1 , wherein the penetration depth relates to the penetration depth within a combustor cavity. 
     
     
         8 . The swirler of  claim 1 , wherein the swirler generates a low net-swirl by co-swirling airflow associated with the outer vane assembly and first middle vane assembly. 
     
     
         9 . The swirler of  claim 1 , further comprising a second middle vane assembly include a plurality of vane elements arranged at a third angle, and wherein the first middle vane assembly is arranged concentrically around the first middle vane assembly. 
     
     
         10 . The swirler of  claim 1 , wherein vanes of the outer vane assembly are angled in a direction opposite to vanes of the first middle vane assembly. 
     
     
         11 . A swirler for a combustor of a gas turbine engine, the swirler comprising:
 an inner passage for receiving a fuel injector;   a plurality of outer passages concentrically arranged around the inner passage, wherein the plurality of outer passages include
 an outer vane assembly including a plurality of vane elements arranged at a first angle; 
 a first middle vane assembly include a plurality of vane elements arranged at a second angle; and 
 a second middle vane assembly include a plurality of vane elements arranged at a third angle, wherein the first middle vane assembly is concentrically arranged around the second middle vane assembly, 
   wherein the outer vane assembly is concentrically arranged around the first middle vane assembly and second middle assembly, and wherein the outer vane assembly, first middle vane assembly and second middle vane assembly are configured to produce a low net-swirl to control the penetration depth of a fuel air mixture for the fuel injector.   
     
     
         12 . The swirler of  claim 11 , wherein the swirler is configured to generate an air and fuel mixture downstream of a combustor pilot flow and improve premixing of the fuel air mixture. 
     
     
         13 . The swirler of  claim 11 , wherein vanes of the outer vane assembly are angled within the range of +45 to +60 degrees. 
     
     
         14 . The swirler of  claim 11 , wherein vanes of the outer vane assembly are arranged and configured to handle within 45 to 65 percent of the airflow received by the swirler. 
     
     
         15 . The swirler of  claim 11 , wherein vanes of the first middle vane assembly are angled within the range of −10 to −30 degrees and vanes of the second middle assembly are angled within the range of +10 to +30 degrees. 
     
     
         16 . The swirler of  claim 11 , wherein vanes of the first middle vane assembly are arranged and configured to handle within 15 to 25 percent of the airflow received by the swirler wherein vanes of the second middle vane assembly are arranged and configured to handle within 15 to 25 percent of the airflow received by the swirler. 
     
     
         17 . The swirler of  claim 11 , wherein the penetration depth relates to the penetration depth within a combustor cavity. 
     
     
         18 . The swirler of  claim 11 , wherein the swirler generates a low net-swirl by co-swirling airflow associated with the outer vane assembly and first middle vane assembly. 
     
     
         19 . The swirler of  claim 11 , further comprising a second middle vane assembly include a plurality of vane elements arranged at a third angle, and wherein the first middle vane assembly is arranged concentrically around the first middle vane assembly. 
     
     
         20 . The swirler of  claim 11 , wherein vanes of the outer vane assembly and second middle vane assembly are angled in a direction opposite to vanes of the first middle vane assembly.