Center tie rotor seal
A turbine engine rotor has a central shaft and a disk stack having disks encircling the shaft. A first piston seal ring in a first groove in the central shaft has an outer diameter (OD) surface facing or contacting an inner diameter (ID) surface of a disk of said plurality of disks. A second piston seal ring in a second OD groove in the central shaft has an OD surface facing or contacting said ID surface of the same said disk. Holes in the central shaft are between the first groove and the second groove. An additional seal is between the first groove and the holes.
1 . A turbine engine rotor comprising:
a central shaft; and
a disk stack having a plurality of disks encircling the shaft,
and further comprising:
a first piston seal ring in a first groove in the central shaft and having an outer diameter (OD) surface facing or contacting an inner diameter (ID) surface of a disk of said plurality of disks;
a second piston seal ring in a second OD groove in the central shaft and having an OD surface facing or contacting said ID surface of the same said disk;
a plurality of holes in the central shaft between the first groove and the second groove; and
an additional seal between the first groove and the plurality of holes.
2 . The turbine engine rotor of claim 1 wherein:
the additional seal is a non-contact seal.
3 . The turbine engine rotor of claim 1 wherein:
the additional seal is selected from the group consisting of finger seals and labyrinth seals.
4 . The turbine engine rotor of claim 3 wherein:
the additional seal is a finger seal with a base mounted to the shaft and fingers projecting radially outward.
5 . The turbine engine rotor of claim 3 wherein:
the additional seal is a labyrinth seal.
6 . The turbine engine rotor of claim 1 wherein:
the shaft has a second plurality of holes axially forward of said second groove and at least partially aft of a bore of a disk immediately forward of said disk.
7 . The turbine engine rotor of claim 6 wherein:
relative to the plurality of holes, the second plurality of holes is smaller in total cross-sectional area.
8 . The turbine engine rotor of claim 1 wherein:
the central shaft has outer diameter surface enhancements between the additional seal and the second OD groove.
9 . The turbine engine rotor of claim 1 wherein:
the outer diameter surface enhancements are a pattern of ridges.
10 . The turbine engine rotor of claim 1 wherein:
the shaft is under axial tension.
11 . The turbine engine rotor of claim 1 wherein:
the first piston seal ring and the second piston seal ring each have a shiplap split.
12 . A gas turbine engine including the turbine engine rotor of claim 1 wherein the rotor is a high pressure compressor rotor and further comprising:
a high pressure turbine rotor co-spooled with the high pressure compressor rotor on a high spool;
a low spool comprising a low pressure compressor rotor and a low pressure turbine rotor;
a combustor; and
a gaspath sequentially through the low pressure compressor, high pressure compressor, combustor, high pressure turbine, and low pressure turbine.
13 . A turbine engine rotor comprising:
a central shaft; and
a disk stack having a plurality of disks encircling the shaft and held in compression by tension in the shaft,
and further comprising:
a first piston seal ring in a first groove in the central shaft and having an outer diameter (OD) surface facing or contacting an inner diameter (ID) surface of a first disk of said plurality of disks;
a second piston seal ring in a second OD groove in the central shaft and having an OD surface facing or contacting said ID surface of the first disk;
a first plurality of holes in the central shaft between the first groove and the second groove; and
a second plurality of holes axially forward of said second groove and at least partially aft of a bore of a second disk immediately forward of said first disk.
14 . The turbine engine rotor of claim 13 wherein:
relative to the first plurality of holes, the second plurality of holes is smaller in total cross-sectional area by at least 50%.
15 . The turbine engine rotor of claim 13 wherein one or both of:
the rotor is a high pressure compressor rotor of a multi-spool engine; and
the second plurality of holes is fully aft of the bore of the second disk.
16 . A turbine engine rotor comprising:
a central shaft; and
a disk stack having a plurality of disks encircling the shaft and held in compression by tension in the shaft,
and further comprising:
a first piston seal ring in a first groove in the central shaft and having an outer diameter (OD) surface facing or contacting an inner diameter (ID) surface of a first disk of said plurality of disks;
a plurality of holes in the central shaft
a non-piston seal ring seal between the first groove and the plurality of holes.
17 . The turbine engine rotor of claim 16 wherein:
the non-piston seal ring seal is a finger seal or a non-contact seal.
18 . The turbine engine rotor of claim 16 wherein:
the non-piston seal ring seal is a finger seal.
19 . The turbine engine rotor of claim 16 wherein:
the non-piston seal ring seal is a labyrinth seal.
20 . The turbine engine rotor of claim 16 further comprising:
a second piston seal ring in a second OD groove in the central shaft and having an OD surface facing or contacting said ID surface of the first disk, the plurality of holes between the non-piston seal ring seal and the second OD groove; and
a second plurality of holes axially forward of said second groove and at least partially aft of a bore of a second disk immediately forward of said first disk.