Stator vane array

Abstract

A stator vane assembly for a gas turbine engine includes circumferentially spaced vanes about a common axis. The array of vanes further includes three or more sub-arrays, which are configured such that the vane spacing in one sub-array is different from the vane spacing in the other sub-arrays.

1 - 16 . (canceled) 
     
     
         17 . A vane assembly for a gas flow machine, the vane assembly comprising an array of vanes circumferentially spaced about a common axis, wherein the array of vanes comprises three or more sub-arrays, wherein the vane spacing within one sub-array is different from the vane spacing within the other sub-arrays; wherein each sub-array comprises a plurality of adjacent vanes, each vane of a sub-array being substantially equally spaced from an adjacent vane in that sub-array. 
     
     
         18 . A vane assembly according to  claim 17 , wherein each sub-array extends through a portion of a revolution about said axis and the sub-arrays are arranged in an end to end arrangement such that the array forms a complete revolution about the axis. 
     
     
         19 . A vane assembly according to  claim 17  wherein a step change in vane spacing occurs upon passage from one sub-array to an adjacent sub-array. 
     
     
         20 . A vane assembly according to  claim 17 , wherein the vane spacing varies in a non-cyclic manner through a single revolution of the array about the axis. 
     
     
         21 . A vane assembly according to  claim 17 , wherein at least a pair of sub-arrays have a vane spacing which differs from an average vane spacing for the array by an equal magnitude. 
     
     
         22 . A vane assembly according to  claim 17 , comprising a casing disposed about the axis, wherein each vane of the array depends inwardly from the casing towards the axis from the casing. 
     
     
         23 . A vane assembly according to  claim 17 , comprising a stator vane assembly for a gas turbine engine. 
     
     
         24 . A gas flow machine comprising:
 a plurality of rows of rotor blades arranged in serial flow arrangement; and   a stator vane assembly disposed in the flow path between said rows of rotor blades,   the rotor blades and stator vane assembly being arranged about a common axis such that the rotor blades can rotate relative to the stator vane assembly in use,   wherein the stator vane assembly comprises an array of vanes circumferentially spaced about a common axis, said array comprising three or more sub-arrays,   wherein each sub-array comprises a plurality of adjacent vanes, each vane of a sub-array being substantially equally spaced from an adjacent vane in that sub-array,   wherein the vane spacing in one sub-array is different from the vane spacing in the other sub-arrays.   
     
     
         25 . A gas flow machine according to  claim 24 , wherein the stator vanes are angled so as to deflect the flow generated by the rotation of an adjacent row of rotor blades. 
     
     
         26 . An axial flow machine according to  claim 24 , wherein said machine comprises a compressor. 
     
     
         27 . A vane assembly according to  claim 24 , wherein each sub-array extends through a portion of a revolution about said axis and the sub-arrays are arranged in an end to end arrangement such that the array forms a complete revolution about the axis. 
     
     
         28 . A vane assembly according to  claim 24 , wherein a step change in vane spacing occurs upon passage from one sub-array to an adjacent sub-array. 
     
     
         29 . A vane assembly according to  claim 24 , wherein the vane spacing varies in a non-cyclic manner through a single revolution of the array about the axis. 
     
     
         30 . A vane assembly according to  claim 24 , wherein at least a pair of sub-arrays have a vane spacing which differs from an average vane spacing for the array by an equal magnitude. 
     
     
         31 . A vane assembly according to  claim 24 , comprising a casing disposed about the axis, wherein each vane of the array depends inwardly from the casing towards the axis from the casing.