Premixer assembly for gas turbine combustor

Abstract

A novel and improved combustion liner for use in a gas turbine engine is provided in which the premixer assembly is removably fastened to the combustion liner. Apparatus and method for removably securing the premixer assembly to the combustion liner is provided. A combustor dome plate, swirler assembly and inlet ring basket are coupled together by a plurality of removable fasteners in order to increase accessibility to portions of the combustion liner for inspection and repair processes.

1 . A premixer assembly for a gas turbine combustor comprising:
 an inlet ring basket having a plurality of lugs, with each of the lugs having an opening extending therethrough;   a plurality of swirler assemblies each for receiving a fuel injector, the swirler assemblies each comprising:
 a premix tube having an inlet end, an opposing outlet end and a longitudinal axis extending therethrough; 
 a premix swirler positioned within the premix tube, the swirler having a plurality of turning vanes for imparting a swirl to a passing flow; 
 a first mounting block positioned along an outer wall of the premix tube proximate the inlet end and having a plurality of first holes oriented generally perpendicular to the longitudinal axis; and, 
 a second mounting block positioned along the outer wall of the premix tube a distance from the first mounting block, the second mounting block has one or more second holes extending through the second mounting block in a direction generally perpendicular to the plurality of first holes; 
   a dome plate spaced an axial distance from the second mounting block of each of the swirler assemblies, and oriented generally parallel to the second mounting block, the dome plate having a plurality of cooling holes; and,   a plurality of fasteners;   wherein the plurality of lugs are positioned axially between the second mounting blocks of the swirler assemblies and the dome plate and the plurality of fasteners pass through the dome plate, the openings in the lugs and the one or more second holes of the second mounting blocks.   
     
     
         2 . The premixer assembly of  claim 1 , wherein the plurality of lugs are integrally formed with the inlet ring basket. 
     
     
         3 . The premixer assembly of  claim 1 , wherein each of the one or more second holes corresponds to one of the plurality of lugs and openings. 
     
     
         4 . The premixer assembly of  claim 1 , wherein each of the swirler assemblies is secured to the inlet basket by a plurality of fasteners. 
     
     
         5 . The premixer assembly of  claim 4 , wherein the plurality of fasteners securing the swirler assemblies to the inlet ring basket are oriented both parallel to and perpendicular to the longitudinal axis of the premix tube of the swirler assemblies. 
     
     
         6 . The premixer assembly of  claim 1 , wherein the holes in the dome plate are oriented parallel to the longitudinal axis of the premix tube. 
     
     
         7 . The premixer assembly of  claim 1 , wherein the holes in the dome plate are oriented at an angle relative to the longitudinal axis of the premix tube. 
     
     
         8 . The premixer assembly of  claim 1 , further comprising a plurality of stand-offs positioned along the premix tube adjacent the outlet end. 
     
     
         9 . A method of assembling a premixer for a gas turbine combustor comprising:
 providing a dome plate having a plurality of fastener openings, an inlet ring basket having a plurality of lugs, each lug having an opening extending therethrough, and a plurality of swirler assemblies, the swirler assemblies each having a first and second mounting block, with the first mounting block having a plurality of first holes and the second mounting block having one or more second holes;   inserting the plurality of swirler assemblies into the inlet ring basket;   placing the dome plate in contact with the plurality of lugs of the inlet ring basket;   inserting the swirler assemblies into corresponding cup openings in the dome plate.   aligning a fastener opening of the dome plate with the opening of a lug and a second hole of the second mounting block;   placing a removable fastener through the fastener opening of the dome plate, the opening of the lug and the second hole of the second mounting block so as to secure the dome plate, lug and second mounting block together.   
     
     
         10 . The method of  claim 9 , wherein the plurality of dome mounting holes are located in an annular array about a perimeter of the dome plate. 
     
     
         11 . The method of  claim 10 , wherein the dome plate further comprises a plurality of cooling holes. 
     
     
         12 . The method of  claim 9 , wherein the plurality of lugs are positioned between the dome plate and the second mounting blocks of the swirler assemblies. 
     
     
         13 . The method of  claim 9 , wherein the one or more second holes in the second mounting block is threaded. 
     
     
         14 . The method of  claim 9 , wherein the swirler assemblies are inserted into the corresponding cup openings such that the second mounting blocks are in contact with the lugs of the inlet ring basket. 
     
     
         15 . The method of  claim 14 , wherein the swirler assemblies are inserted in the corresponding cup openings such that a plurality of stand-offs positioned along an outer surface of the premix tube contact the dome plate. 
     
     
         16 . The method of  claim 9 , wherein a tightening of the removable fastener draws the second mounting block and the dome plate toward the lug of the inlet ring basket. 
     
     
         17 . An interface joint for coupling components of a premixer assembly comprising:
 an inlet ring basket having a lug where the lug has an opening extending therethrough;   a swirler assembly having a premix tube, a premix swirler positioned within the premix tube, and a mounting block positioned along an outer wall of the premix tube and having one or more holes extending through the mounting block in a direction parallel to the premix tube;   a dome plate having a plurality of cooling holes; and,   one or more fasteners for securing the lug, mounting block and dome plate together.   
     
     
         18 . The interface joint of  claim 17 , wherein the inlet ring basket has a plurality of lugs located in an annular array about the inlet ring basket. 
     
     
         19 . The interface joint of  claim 17 , wherein the plurality of fasteners are removable. 
     
     
         20 . The interface joint of  claim 17 , wherein the fasteners draw the mounting block and the dome plate towards the lug of the inlet ring basket.