Blade element cross-ties

Abstract

A blade element and methods of manufacturing blade elements are provided for blade elements of a gas turbine engine. In one embodiment, a blade element includes a first inner surface of the blade element, wherein the first inner surface is associated with a first outer blade surface of the blade element, and a second inner surface of the blade element, wherein the second inner surface is associated with a second outer blade surface of the blade element and wherein the second inner surface is opposite from the first inner surface. The blade element may also include a cross-tie configured to connect the first inner surface to the second inner surface, wherein the cross-tie is positioned along a trailing edge of the blade element and the cross-tie is configured to reduce vibration mode effects of the blade element.

What is claimed is: 
     
         1 . A blade element for a gas turbine engine, the blade element comprising:
 a first inner surface of the blade element, wherein the first inner surface is associated with a first outer blade surface of the blade element;   a second inner surface of the blade element, wherein the second inner surface is associated with a second outer blade surface of the blade element and wherein the second inner surface is opposite from the first inner surface; and   a cross-tie configured to connect the first inner surface to the second inner surface, wherein the cross-tie is positioned along a trailing edge of the blade element and the cross-tie is configured to reduce vibration mode effects of the blade element.   
     
     
         2 . The blade element of  claim 1 , wherein the cross-tie includes a first portion blended to the first inner surface, a second portion blended to the second inner surface, and a non-circular cross-section between the first and second portions. 
     
     
         3 . The blade element of  claim 2 , wherein the non-circular cross-section is reduced in size relative to the first and second portions of the cross-tie. 
     
     
         4 . The blade element of  claim 2 , wherein the non-circular cross-section is formed to include a non-circular blend between first and second portions of the cross-tie blended to blade surfaces. 
     
     
         5 . The blade element of  claim 1 , wherein the cross-tie includes a long axis oriented with the direction of centrifugal pull of the blade element. 
     
     
         6 . The blade element of  claim 1 , wherein the cross-tie increases stability of the blade element by supporting the first and second blade element surfaces in a hollow section of the blade element. 
     
     
         7 . The blade element of  claim 1 , wherein the second inner surface is opposite from the first inner surface within at least one of cooling passage and hollow portion of the blade element. 
     
     
         8 . The blade element of  claim 1 , wherein vibration mode effects include at least one of blade surface stress, blade surface strain, vibratory stress, vibratory strain, and blade deformation. 
     
     
         9 . The blade element of  claim 1 , wherein blade element includes a plurality of cross-ties along the trailing edge of the blade element. 
     
     
         10 . The blade element of  claim 9 , wherein cross-ties of the blade element are positioned between 20-90% of a span length of the blade element. 
     
     
         11 . A method for fabricating a blade element of a gas turbine engine, the method comprising:
 forming a first blade surface of the blade element, wherein the first blade surface includes a first inner surface;   forming a second blade surface of the blade element, wherein the second blade surface includes a second inner surface and wherein the second inner surface is opposite from the first inner surface; and   forming a cross-tie configured to connect the first inner surface to the second inner surface along a trailing edge of the blade element, wherein the cross-tie is positioned and configured to reduce vibration mode effects of the blade element.   
     
     
         12 . The method of  claim 11 , wherein the cross-tie includes a first portion blended to the first inner surface, a second portion blended to the second inner surface, and a non-circular cross-section between the first and second portions. 
     
     
         13 . The method of  claim 12 , wherein the non-circular cross-section is reduced in size relative to the first and second portions of the cross-tie. 
     
     
         14 . The method of  claim 12 , wherein the non-circular cross-section is formed to include a non-circular blend between first and second portions of the cross-tie blended to blade surfaces. 
     
     
         15 . The method of  claim 11 , wherein the cross-tie includes a long axis oriented with the direction of centrifugal pull of the blade element. 
     
     
         16 . The method of  claim 11 , wherein the cross-tie increases stability of the blade element by supporting the first and second blade element surfaces in at least one of a cooling passage and hollow portion of the blade element. 
     
     
         17 . The method of  claim 11 , wherein forming cross-ties includes forming a plurality of cross-ties along the trailing edge of the blade element. 
     
     
         18 . The method of  claim 17 , wherein cross-ties of the blade element are positioned between 20-90% of a span length of the blade element. 
     
     
         19 . The method of  claim 11 , further comprising determining one or more cross-tie locations for the blade element. 
     
     
         20 . The method of  claim 19 , wherein determining one or more cross-tie locations for the blade element includes modeling a blade element for one or more of vibratory frequency, vibratory mode shape and vibratory stress.