Inter-blade sealing for a turbine or compressor wheel of a turbine engine
An inter-blade sealing for a turbine or compressor wheel of a turbine engine includes inserts engaged in longitudinal cavities in side edges of platforms of blades and bearing, in operation, against facing side edges of platforms of adjacent blades. Each insert has a cylindrical elongate shape and includes in its outer cylindrical surface at least one annular groove for passing platform cooling air.
1. A turbine or compressor wheel for a turbine engine, comprising:
inter-blade sealing means comprising inserts engaged in longitudinal cavities in side edges of platforms of blades and bearing in operation against facing side edges of platforms of adjacent blades, each insert being in a form of an elongate cylinder and including at least one annular groove in an outer cylindrical surface thereof for passing air for cooling the platforms of the blades,
wherein the inserts include at least one annular score in the outer cylindrical surface forming a wear indicator, a depth of the annular score being less than a depth of the annular groove for passing cooling air, and
wherein each insert is cylindrical in shape between a first end and a second end of the respective insert, and the at least one annular groove and the at least one annular score are both formed around the entire outer cylindrical surface of the respective insert.
2. A wheel according to claim 1 , wherein each insert includes two annular scores disposed in a vicinity of each end of the insert.
3. A wheel according to claim 1 , wherein each insert includes one, two, or three annular grooves for passing platform cooling air.
4. A wheel according to claim 1 , wherein each insert has a diameter of about 2 mm to 3 mm and a length of about 20 mm to 40 mm.
5. A wheel according to claim 4 , wherein each annular groove for passing platform cooling air has a width of about 0.5 mm and a depth of about 0.6 mm.
6. A wheel according to claim 4 , wherein each annular score forming a wear indicator has a width of about 0.2 mm and a depth of about 0.2 mm.
7. A wheel according to claim 1 , wherein each insert is made of a metal alloy, of a superalloy, or of a ceramic matrix composite material.
8. A wheel according to claim 1 , further comprising a disk carrying the blades, each blade having a root engaged in a slot of complementary shape in a periphery of the disk, and a platform that connects the root to an airfoil of the blade and that includes two substantially parallel side edges,
wherein the side edge of the platform extending beside a pressure side of the airfoil of each blade includes a longitudinal cavity for receiving an insert.
9. A wheel according to claim 8 , wherein the cavity for receiving the sealing means has a U-shaped or V-shaped section at longitudinal ends thereof, an open side of the U- or V-shaped section facing towards the adjacent blade, a radially inner side wall of the cavity extending substantially parallel to the platform and a radially outer side wall of the cavity being inclined relative to the platform and extending radially outwards beside the adjacent blade.