Turbine Nozzle-To-Shroud Interface

Abstract

A turbomachine includes a compressor, a combustor, and a turbine. The turbine includes a nozzle, a shroud, and an axial cavity defined between the nozzle and the shroud. The nozzle includes an inner platform, an outer platform spaced apart from the inner platform along a radial direction, and an airfoil extending therebetween. The outer platform extends axially between a forward sidewall and an aft sidewall. The nozzle also includes an aft hook radially outward of the outer platform and axially forward of the aft sidewall of the outer platform. The shroud includes a forward end adjacent to the aft sidewall of the outer platform. A sealing interface is positioned within the cavity, radially outward of the outer platform of the nozzle and axially forward of the aft sidewall of the outer platform of the nozzle.

What is claimed is: 
     
         1 . A gas turbine, the gas turbine comprising a central axis, the central axis of the gas turbine defines an axial direction, a radial direction perpendicular to the central axis, and a circumferential direction extending around the central axis, the gas turbine further comprising:
 a compressor;   a combustor downstream of the compressor;   a turbine section downstream of the combustor, the turbine section comprising:
 a nozzle comprising:
 an inner platform; 
 an outer platform spaced apart from the inner platform along a radial direction, the outer platform extending along an axial direction between a forward sidewall and an aft sidewall; 
 an airfoil extending between the inner platform and the outer platform, the airfoil comprising a leading edge at a forward end of the airfoil and a trailing edge at an aft end of the airfoil; and 
 an aft hook radially outward of the outer platform and axially forward of the aft sidewall of the outer platform; 
 
 a shroud extending between a forward end and an aft end, the forward end of the shroud adjacent to the aft sidewall of the outer platform, the shroud comprising a forward hook, the forward hook of the shroud configured to engage with the aft hook of the nozzle to support the nozzle; 
 a cavity defined by an axial clearance between the nozzle and the shroud; and 
 a sealing interface within the cavity, the sealing interface radially outward of the outer platform of the nozzle and axially forward of the aft sidewall of the outer platform of the nozzle. 
   
     
     
         2 . The gas turbine of  claim 1 , wherein the airfoil of the nozzle defines a wake pressure zone aft of the trailing edge, and the aft sidewall of the outer platform is positioned aft of the wake pressure zone. 
     
     
         3 . The gas turbine of  claim 1 , wherein the cavity defines a tortuous flow path. 
     
     
         4 . The gas turbine of  claim 1 , wherein the nozzle comprises a heat-resistant super alloy material. 
     
     
         5 . The gas turbine of  claim 1 , wherein the shroud comprises a stainless steel material. 
     
     
         6 . A turbine for a turbomachine, the turbine comprising:
 a nozzle comprising:
 an inner platform; 
 an outer platform spaced apart from the inner platform along a radial direction, the outer platform extending along an axial direction between a forward sidewall and an aft sidewall; and 
 an airfoil extending between the inner platform and the outer platform, the airfoil comprising a leading edge at a forward end of the airfoil and a trailing edge at an aft end of the airfoil; 
   a shroud extending between a forward end and an aft end, the forward end of the shroud adjacent to the aft sidewall of the outer platform;   a cavity defined by an axial clearance between the nozzle and the shroud; and   a sealing interface within the cavity, the sealing interface radially outward of the outer platform of the nozzle and axially forward of the aft sidewall of the outer platform of the nozzle.   
     
     
         7 . The turbine of  claim 6 , wherein the nozzle further comprises an aft hook positioned outward of the outer platform, the aft hook forward of the aft sidewall of the outer platform. 
     
     
         8 . The turbine of  claim 6 , wherein the nozzle further comprises an aft hook positioned outward of the outer platform, the aft hook forward of the trailing edge of the airfoil. 
     
     
         9 . The turbine of  claim 6 , wherein the airfoil of the nozzle defines a wake pressure zone aft of the trailing edge, and the aft sidewall of the outer platform is positioned aft of the wake pressure zone. 
     
     
         10 . The turbine of  claim 6 , wherein the cavity defines a tortuous flow path. 
     
     
         11 . The turbine of  claim 6 , wherein the nozzle comprises a heat-resistant super alloy material. 
     
     
         12 . The turbine of  claim 6 , wherein the shroud comprises a stainless steel material. 
     
     
         13 . A turbine for a turbomachine, the turbine comprising:
 a nozzle comprising:
 an inner platform; 
 an outer platform spaced apart from the inner platform along a radial direction, the outer platform extending along an axial direction between a forward sidewall and an aft sidewall; 
 an airfoil extending between the inner platform and the outer platform, the airfoil comprising a leading edge at a forward end of the airfoil and a trailing edge at an aft end of the airfoil; and 
 an aft hook radially outward of the outer platform and axially forward of the trailing edge of the airfoil; 
   a shroud extending between a forward end and an aft end, the forward end of the shroud adjacent to the aft sidewall of the outer platform, the shroud comprising a forward hook, the forward hook of the shroud configured to engage with the aft hook of the nozzle to support the nozzle; and   a cavity defined by an axial clearance between the nozzle and the shroud.   
     
     
         14 . The turbine of  claim 13 , further comprising a sealing interface between the nozzle and the shroud, the sealing interface radially outward of the outer platform of the nozzle and axially forward of the aft sidewall of the outer platform of the nozzle. 
     
     
         15 . The turbine of  claim 13 , wherein the airfoil of the nozzle defines a wake pressure zone aft of the trailing edge, and the aft sidewall of the outer platform is positioned aft of the wake pressure zone. 
     
     
         16 . The turbine of  claim 13 , wherein the cavity defines a tortuous flow path. 
     
     
         17 . The turbine of  claim 13 , wherein the nozzle comprises a heat-resistant super alloy material. 
     
     
         18 . The turbine of  claim 13 , wherein the shroud comprises a stainless steel material.