Airfoil for inlet guide vane (igv) of multistage compressor

Abstract

A vane for an Inlet Guide Vane (IGV) of a multistage compressor includes a root portion, a tip portion, and an airfoil extending therebetween. The vane is configured such that a ratio of the maximum thickness of the airfoil to a chord length (T max /C) at 50% of the span height (H) taken from the tip portion of the vane is configured to lie in the range of 0.11 to 0.12. In addition to the ratio (T max /C) at 50% of the span height (H) being in range of 0.11 to 0.12, a ratio of the maximum thickness to the chord length (T max /C) at various points along the airfoil varies with span height (H) of the vane i.e., distance taken from the tip portion of the vane and the local chord length C present at that span height H of the vane taken from the tip portion.

What is claimed is: 
     
         1 . A vane for an Inlet Guide Vane (IGV) of a multistage compressor, the vane comprising:
 a root portion;   a tip portion located distally from the root portion with a span height (H) defined therebetween; and   an airfoil extending longitudinally between the root portion and the tip portion, wherein a ratio of the maximum thickness of the airfoil to the chord length (T max /C) at 50% of the span height (H) taken from the tip portion of the vane is configured to lie in the range of 0.11 to 0.12.   
     
     
         2 . The vane of  claim 1  further including a leading edge and a trailing edge transversely disposed at opposing ends of the root portion, the tip portion, and the airfoil, wherein the leading edge and the trailing edge are separated by the chord length (C) defined therebetween. 
     
     
         3 . The vane of  claim 1 , wherein a ratio of the maximum thickness of the airfoil to the chord length (T max /C) at the tip portion is configured to lie in the range of 0.09 to 0.10. 
     
     
         4 . The vane of  claim 2 , wherein a ratio of the maximum thickness of the airfoil to the chord length (T max /C) is configured to lie in the range of 0.09 to 0.10 at:
 10% of the span height (H) taken from the tip portion of the vane;   40% of the span height (H) taken from the root portion; and   60% of the span height (H) taken from the tip portion of the vane.   
     
     
         5 . The vane of  claim 2 , wherein a ratio of the maximum thickness of the airfoil to the chord length (T max /C) is configured to lie in the range of 0.08 to 0.09 at:
 20% of the span height (H) taken from the tip portion of the vane; and   90% of the span height (H) taken from the tip portion of the vane.   
     
     
         6 . The vane of  claim 2 , wherein a ratio of the maximum thickness of the airfoil to the chord length (T max /C) is configured to lie in the range of 0.07 to 0.08 at:
 30% of the span height (H) taken from the tip portion of the vane; and   80% of the span height (H) taken from the tip portion of the vane.   
     
     
         7 . The vane of  claim 2 , wherein a ratio of the maximum thickness of the airfoil to the chord length (T max /C) at 70% of the span height (H) taken from the tip portion of the vane is configured to lie in the range of 0.065 to 0.075. 
     
     
         8 . The vane of  claim 2 , wherein a ratio of the maximum thickness of the airfoil to the chord length (T max /C) at the root portion is configured to lie in the range of 0.10 to 0.11. 
     
     
         9 . The vane of  claim 1 , wherein the maximum thickness (T max ) of the airfoil across the span height H is selected so as to configure the vane with a natural frequency lying outside a range of operational frequencies of the vane. 
     
     
         10 . A method for manufacturing a vane for an Inlet Guide Vane (IGV) of a multistage compressor, the method comprising:
 forming a root portion of the vane   forming a tip portion distally located from the root portion with a span height (H) defined therebetween;   forming an airfoil extending longitudinally between the root portion and the tip portion such that a ratio of the maximum thickness of the airfoil to a chord length (T max /C) at 50% of the span height (H) taken from the tip portion of the vane is in the range of 0.11 to 0.12   
     
     
         11 . The method of  claim 10  further including forming a leading edge and a trailing edge so as to be transversely disposed at opposing ends of the root portion, the tip portion, and the airfoil, wherein the leading edge and the trailing edge define the chord length (C) therebetween. 
     
     
         12 . The method of  claim 11 , wherein forming the airfoil includes forming the airfoil such that a ratio of the maximum thickness of the airfoil to the chord length (T max /C) at the tip portion of the vane is in the range of 0.09 to 0.10. 
     
     
         13 . The method of  claim 11 , wherein forming the airfoil includes forming the airfoil such that a ratio of the maximum thickness of the airfoil to the chord length (T max /C) is configured to lie in the range of 0.09 to 0.10 at:
 10% of the span height (H) taken from the tip portion of the vane;   40% of the span height (H) taken from the tip portion of the vane; and   60% of the span height (H) taken from the tip portion of the vane.   
     
     
         14 . The method of  claim 11 , wherein forming the airfoil includes forming the airfoil such that a ratio of the maximum thickness of the airfoil to the chord length (T max /C) is configured to lie in the range of 0.08 to 0.09 at:
 20% of the span height (H) taken from the tip portion of the vane; and   90% of the span height (H) taken from the tip portion of the vane.   
     
     
         15 . The method of  claim 11 , wherein forming the airfoil includes forming the airfoil such that a ratio of the maximum thickness of the airfoil to the chord length (T max /C) is configured to lie in the range of 0.07 to 0.08 at:
 30% of the span height (H) taken from the tip portion of the vane; and   80% of the span height (H) taken from the tip portion of the vane.   
     
     
         16 . The method of  claim 11 , wherein forming the airfoil includes forming the airfoil such that a ratio of the maximum thickness of the airfoil to the chord length (T max /C) at 70% of the span height (H) taken from the tip portion of the vane is in the range of 0.065 to 0.075. 
     
     
         17 . The method of  claim 11 , wherein forming the airfoil includes forming the airfoil such that a ratio of the maximum thickness of the airfoil to the chord length (T max /C) at the root portion is in the range of 0.10 to 0.11. 
     
     
         18 . The method of  claim 10 , wherein forming the airfoil includes selecting the maximum thickness (T max ) of the airfoil across the span height H such that the vane is configured with a natural frequency lying outside a range of operational frequencies of the vane.