Controlled gap seal with surface discontinuities
There is disclosed a controlled gap seal for a gas turbine engine including a ring configured to be in a sealing engagement with a housing and a runner configured for rotation relative to the ring about the central axis. The runner has a runner face facing a ring face of the ring. The ring face is spaced apart from the runner face by a gap. A plurality of surface discontinuities are circumferentially distributed around the central axis on the runner face and/or the ring face. The plurality of surface discontinuities are spaced relative to one another such that a first set of adjacent surface discontinuities are circumferentially spaced from each other at a different distance than a second set of adjacent surface discontinuities. A method of using the controlled gap seal is disclosed.
1. A controlled gap seal for a gas turbine engine, comprising:
a ring configured to be in a sealing engagement with a housing, the ring annularly and continuously extending about a central axis;
a runner configured for rotation relative to the ring about the central axis, the runner having a runner face facing a ring face of the ring, the ring face spaced apart from the runner face by a gap; and
a plurality of surface discontinuities being tabs circumferentially distributed around the central axis and extending from the runner face and/or the ring face, the plurality of surface discontinuities spaced relative to one another such that a first set of adjacent surface discontinuities are circumferentially spaced from each other at a different distance than a second set of adjacent surface discontinuities.
2. The controlled gap seal of claim 1 , wherein the tabs have a cylindrical shape.
3. The controlled gap seal of claim 1 , wherein the surface discontinuities further include grooves.
4. The controlled gap seal of claim 3 , wherein the grooves have a square cross-section.
5. The controlled gap seal of claim 1 , wherein the surface discontinuities are located on both of the runner face and the ring face.
6. The controlled gap seal of claim 1 , comprising additional surface discontinuities being located on a face of the housing that is oriented toward the runner.
7. The controlled gap seal of claim 1 , wherein a height of the surface discontinuities along a radial direction relative to the central axis is less than that of the gap.
8. A controlled gap seal for a gas turbine engine, comprising:
a ring configured to be in a sealing engagement with a housing, the ring annularly and continuously extending about a central axis;
a runner configured for rotation relative to the ring about the central axis, the runner having a runner face facing a ring face of the ring, the ring face spaced apart from the runner face by a gap; and
a plurality of surface discontinuities circumferentially distributed around the central axis and on the runner face and/or the ring face, the plurality of surface discontinuities spaced relative to one another such that a first set of adjacent surface discontinuities are circumferentially spaced from each other at a different distance than a second set of adjacent surface discontinuities, for each two adjacent ones of the surface discontinuities, a channel is defined therebetween, the channel extending in both an axial direction relative to the central axis and a circumferential direction.
9. The controlled gap seal of claim 8 , wherein a height of the surface discontinuities along a radial direction relative to the central axis is less than that of the gap.
10. The controlled gap seal of claim 8 , wherein the surface discontinuities are located on both of the runner face and the ring face.
11. The controlled gap seal of claim 8 , wherein the surface discontinuities are tabs extending from the runner face and/or the ring face.
12. A controlled gap seal for a gas turbine engine, comprising:
a ring sealingly engaged to a housing, the ring annularly and continuously extending about a central axis;
a runner configured for rotation relative to the ring about the central axis, the runner having a runner face facing a ring face of the ring, the ring face spaced apart from the runner face by a gap; and
a plurality of surface discontinuities circumferentially distributed around the central axis on the ring face, the plurality of surface discontinuities spaced relative to one another such that a first set of adjacent surface discontinuities are circumferentially spaced from each other at a different distance than a second set of adjacent surface discontinuities.
13. The controlled gap seal of claim 12 , comprising additional surface discontinuities on a face of the housing and/or on the runner face.
14. The controlled gap seal of claim 12 , wherein the surface discontinuities are tabs extending from the face of the housing.
15. The controlled gap seal of claim 14 , wherein the tabs have a cylindrical shape.
16. The controlled gap seal of claim 12 , wherein the surface discontinuities further include grooves.
17. The controlled gap seal of claim 16 , wherein the grooves have a square cross-section.
18. The controlled gap seal of claim 12 , wherein, for each two adjacent ones of the surface discontinuities, a channel is defined therebetween, the channel extending in an axial direction relative to the central axis.
19. The controlled gap seal of claim 18 , wherein the channel further extends in a circumferential direction relative to the central axis.
20. The controlled gap seal of claim 12 , wherein a height of the surface discontinuities along a radial direction relative to the central axis is less than that of the gap.