Turbine engine nozzle

Abstract

A turbine engine nozzle assembly has an upstream flap assembly having a main flap and a liner, a cooling passageway formed between the main flap and liner. A downstream flap is pivotally coupled to the upstream flap assembly for relative rotation about a hinge axis. The liner has a trailing end spaced upstream from a trailing end of the main flap by at least 40% of a length of the main flap.

1 . A turbine engine nozzle subassembly comprising: 
 an upstream flap assembly having a main flap and a liner, a cooling passageway formed between the main flap and liner;    a downstream flap pivotally coupled to the upstream flap for relative rotation about a hinge axis; and    an actuator linkage coupled to at least one of the upstream flap and the downstream flap for actuating the upstream and downstream flaps between a plurality of throat area conditions,    wherein:    the liner has a trailing end spaced upstream from a trailing end of the main flap by at least 40% of a length of the main flap.    
   
   
       2 . The subassembly of  claim 1  further comprising: 
 an external flap pivotally coupled to the downstream flap and to an environmental structure so that a span between respective coupling locations with said downstream flap and environmental structure is extensible and contractable responsive to aerodynamic forces.    
   
   
       3 . The subassembly of  claim 1  wherein the liner comprises: 
 a liner body; and    a liner mounting bracket secured to the liner body and to the main flap.    
   
   
       4 . The subassembly of  claim 3  wherein: 
 the liner body comprises an Nb-based sheet and a Ni-based superalloy backing element.    
   
   
       5 . The subassembly of  claim 1  wherein: 
 the liner trailing end is spaced upstream from the main flap trailing end of the main flap by 70-80% of the length of the main flap.    
   
   
       6 . The subassembly of  claim 1  wherein: 
 the liner has a length of 15-50% of the length of the main flap.    
   
   
       7 . The subassembly of  claim 1  wherein: 
 the liner has a length of 20-30% of the length of the main flap.    
   
   
       8 . A turbine engine nozzle comprising: 
 a static structure;    a plurality of flap subassemblies comprising: 
 an upstream main flap pivotally coupled to the static structure for relative rotation about an axis essentially fixed relative to the static structure; and  
 a downstream flap pivotally coupled to the upstream flap for relative rotation about a hinge axis; and  
   a liner along the upstream main flaps and forming a generally annular cooling air passageway, the cooling passageway having an outlet spaced upstream of a downstream end of the main flaps by a longitudinal distance of at least 40% of a longitudinal length of the upstream main flaps.    
   
   
       9 . The nozzle of  claim 8  wherein: 
 the plurality of flap subassemblies are axisymmetrically arranged about an engine centerline;    said articulation is simultaneous for each of the flap subassemblies; and    each of the plurality of flap subassemblies further comprises an external flap pivotally coupled to the downstream flap.    
   
   
       10 . The nozzle of  claim 8  wherein the liner comprises a circumferential array of: 
 a plurality of first members, each mounted to an associated one of the main flaps; and    a plurality of second members, each between an associated pair of the first members and mounted to an associated convergent seal.    
   
   
       11 . A turbine engine nozzle comprising: 
 a static structure;    a convergent section comprising: 
 a circumferential array of first flaps, each pivotally coupled to the static structure;  
 a circumferential array of first seals, alternatingly interspersed with the first flaps; and  
 a liner assembly;  
   a divergent section comprising: 
 a circumferential array of second flaps, each pivotally coupled to an associated one of the first flaps; and  
 a circumferential array of second seals, alternatingly interspersed with the second flaps,  
 wherein  
   the liner has an outlet spaced upstream of a downstream end of the main flaps by a longitudinal distance of essentially at least 40% of a longitudinal length of the convergent section.    
   
   
       12 . A gas turbine engine nozzle convergent section liner member comprising: 
 a panel having: 
 an inboard surface;  
 an outboard surface;  
 a leading end;  
 a trailing end  
 first and second lateral ends;  
 a length between the leading end and the trailing end; and  
 a lateral span between the first and second lateral ends,  
 wherein:  
   the lateral span is greater than the length.    
   
   
       13 . The liner member of  claim 12  wherein: 
 the length is 40-60% of the lateral span.    
   
   
       14 . The liner member of  claim 12  wherein: 
 the panel has: 
 a generally planar central portion; and  
 means along the first and second lateral edges for interfitting with complementary features of a complementary panel.  
   
   
   
       15 . The liner member of  claim 12  further comprising: 
 a mounting bracket secured to the panel and extending from the outboard surface and having: 
 a central web essentially parallel and spaced apart from a central portion of the panel and having a bolting aperture; and  
 first and second lateral webs extending toward the panel from first and second edges of the central web.  
   
   
   
       16 . The liner member of  claim 12  wherein: 
 the panel comprises a liner sheet, a backing sheet along only an upstream portion of the liner sheet, and a deflector;    a plurality of rivets securing the liner sheet, backing sheet, and deflector; and    a pair of welds secure the mounting bracket to the liner sheet.    
   
   
       17 . A method for retrofitting a turbine engine or reengineering a turbine engine configuration which engine or configuration has or has previously had a first nozzle subassembly having a convergent flap, a divergent flap, an external flap, and an actuation linkage coupled to the convergent flap, the method comprising: 
 replacing a first liner member of the convergent flap with a second liner member, the second liner member having a downstream end positioned upstream from a former position of a downstream end of the first liner member by at least 10% of a length of the convergent flap.    
   
   
       18 . The method of  claim 17  wherein: 
 said second liner member provides a higher coolant-to-gas ρv ratio than was provided by the first liner member.    
   
   
       19 . The method of  claim 17  wherein: 
 said second liner member comprises a liner sheet and a mounting bracket welded to the liner sheet.    
   
   
       20 . The method of  claim 17  wherein: 
 a plurality of such first liner members of a circumferential array of such first nozzle subassemblies are replaced with a plurality of such second liner members.