Axial Turbomachine Stator with Segmented Inner Shell

Abstract

The present application relates to a compressor stator of an axial turbomachine having an inner shell formed of a plurality of annular segments arranged end to end, a layer of abradable material applied on the inner face of the shell, and an annular array of blades connected to the shell. The stator has at least one strip located in the layer of abradable material and extending from either side of the junctions between two adjacent annular segments. The inner tips of the blades have hooks mating mechanically with the strip.

1 . A stator of a compressor of an axial turbomachine, comprising:
 an annular ring of blades extending radially;   an inner shell through which the inner tips of the blades pass, the shell comprising annular segments arranged end to end; and   at least one strip extending circumferentially along the length of the inner surface of the shell and mating with an engaging member for engaging the inner tips of the blades for retention thereof, each strip extending continuously along at least two adjacent annular segments.   
     
     
         2 . The stator in accordance with  claim 1 , wherein each strip is spaced from the inner surface of the shell, the surface being covered with a layer of abradable material embedding each strip. 
     
     
         3 . The stator in accordance with  claim 1 , wherein at least one of the strips has a flat solid section. 
     
     
         4 . The stator in accordance with  claim 1 , wherein each of the strips extends over at least a quarter of each of two adjacent annular segments. 
     
     
         5 . The stator in accordance with  claim 1 , wherein each of the strips extends over at least a third of each of two adjacent annular segments. 
     
     
         6 . The stator in accordance with  claim 1 , wherein each of the strips extends over at least a half of each of two adjacent annular segments. 
     
     
         7 . The stator in accordance with  claim 1 , wherein the strip forms an open ring. 
     
     
         8 . The stator in accordance with  claim 1 , wherein the engaging member of the inner tips of the blades comprises:
 openings mating with the strips.   
     
     
         9 . The stator in accordance with  claim 1 , wherein the engaging member of the inner tips of the blades comprises:
 hooks mating with the strips.   
     
     
         10 . The stator in accordance with  claim 1 , wherein the engaging member is spaced upstream and downstream of the shell, being essentially central in the shell in an axial direction. 
     
     
         11 . The stator in accordance with  claim 1 , wherein the portions of the engaging member mating with the strips has lengths in an axial direction which are more than 100% the width of the strips, so as to allow a variation of positioning of engaging member along the said direction. 
     
     
         12 . The stator in accordance with  claim 1 , wherein the portions of the engaging member mating with the strips has lengths in an axial direction which are more than 200% the width of the strips, so as to allow a variation of positioning of engaging member along the said direction. 
     
     
         13 . The stator in accordance with  claim 1 , wherein the strips have an annular profile matching that of the profile of the shell. 
     
     
         14 . The stator in accordance with  claim 13 , wherein the profile of the strips between two adjacent blades matches that of the shell. 
     
     
         15 . The stator in accordance with  claim 1 , wherein the shell comprises:
 at least four annular segments;   wherein the strips span at least a quarter of the inner shell.   
     
     
         16 . The stator in accordance with  claim 1 , wherein the shell comprises:
 at least four annular segments;   wherein the strips span the entire inner shell.   
     
     
         17 . The stator in accordance with  claim 1 , wherein the strips are made of a metallic material chosen from the group:
 titanium;   steel; or   aluminium.   
     
     
         18 . The stator in accordance with  claim 1 , wherein the engaging member comprises:
 hooks whose throats are oriented in an axial direction.   
     
     
         19 . The stator in accordance with  claim 18 , wherein the hooks have lips at the throats thereof for restraining the strips axially. 
     
     
         20 . A compressor of an axial turbomachine, comprising:
 a low pressure compressor;   an annular ring of blades extending radially;   an inner shell through which the inner tips of the blades pass, the shell comprising annular segments arranged end to end; and   at least one strip extending circumferentially along the length of the inner surface of the shell and mating with a engaging member the inner tips of the blades for their retention, each strip extending continuously along at least two adjacent annular segments.