Seal runner

Patent metadata

Field	Value
Publication number	US-2016169019-A1
Application number	US-201414570325-A
Country	US
Kind code	A1
Filing date	Dec 15, 2014
Priority date	Dec 15, 2014
Publication date	Jun 16, 2016
Grant date	—

Abstract

A seal runner for a gas turbine engine, the seal runner including an annular body having a sealed cavity defined therein, the cavity being elongated along an axial direction of the body and being annular, the cavity at least partially filled with a coolant, the coolant being liquid across a range of operating temperatures of the gas turbine engine, the coolant having a temperature dependent density across the range of operating temperatures of the gas turbine engine. A gas turbine engine and a method of cooling a seal runner exposed to a temperature gradient are also discussed.

First claim

1 . A seal runner for a gas turbine engine, the seal runner comprising:
an annular body having a sealed cavity defined therein, the cavity being elongated along an axial direction of the body and being annular, the cavity at least partially filled with a coolant, the coolant being liquid across a range of operating temperatures of the gas turbine engine, the coolant having a temperature dependent density across the range of operating temperatures of the gas turbine engine.

2 . The seal runner as defined in claim 1 , wherein the range of operating temperatures is at least from about −50 deg.C to 230 deg.C.

3 . The seal runner as defined in claim 2 , wherein the range of operating temperatures is at least from about 75 deg.C to 230 deg.C.

4 . The seal runner as defined in claim 1 , wherein the coolant is a metal, a metal alloy or a salt.

5 . The seal runner as defined in claim 1 , wherein the cavity has an inner wall and an outer wall disposed radially outwardly from the inner wall, the inner wall being stepped.

6 . The seal runner as defined in claim 1 , wherein the cavity includes a main cavity portion and an auxiliary cavity portion opened into the main cavity portion, the auxiliary cavity portion being disposed radially inwardly from the main cavity portion, the auxiliary cavity portion having an axial length shorter than an axial length of the main cavity portion. The seal runner as defined in claim 1 , wherein the coolant is solid at ambient temperature.

8 . The seal runner as defined in claim 1 , wherein the cavity is completely filled with the coolant.

9 . A gas turbine engine comprising:
a rotatable shaft having an axially extending rotational axis; a seal runner connected around the shaft to rotate therewith, the seal runner in sealing engagement with at least one static seal, the seal runner including:
an annular body including a sealed cavity filled at least partially with a coolant, the cavity being axially elongated and annular, the coolant being liquid across a range of operating temperatures of the gas turbine engine, the coolant having a temperature dependent density across the range of operating temperatures of the gas turbine engine, whereby when the gas turbine engine is in operation, a temperature gradient is defined across the seal runner and rotation of the seal runner recirculates the liquid coolant within the sealed cavity.

10 . The seal runner as defined in claim 9 , wherein the range of operating temperatures is at least from about −50 deg.C to 230 deg.C.

11 . The seal runner as defined in claim 10 , wherein the range of operating temperatures is at least from about 75 deg.C to 230 deg.C.

12 . The gas turbine engine as defined in claim 9 , wherein the temperatures gradient is axially oriented, and the coolant recirculates in the cavity generally axially.

13 . The gas turbine engine as defined in claim 9 , wherein the coolant is a metal, a metal alloy or a salt.

14 . The gas turbine engine as defined in claim 9 , wherein the cavity has an inner wall and an outer wall disposed radially outwardly from the inner wall, the inner wall being stepped.

15 . The gas turbine engine as defined in claim 9 , wherein the cavity includes a main cavity portion and an auxiliary cavity portion opened into the main cavity portion so that the recirculation takes place across the main cavity portion and the auxiliary cavity portion, the auxiliary cavity portion being disposed radially inwardly from the main cavity portion, the auxiliary cavity portion having an axial length shorter than an axial length of the main cavity portion.

16 . The gas turbine engine as defined in claim 15 , wherein the cavity extends axially between a first end and a second end, and the main cavity portion extends axially between the first end and the second end, and the auxiliary cavity portion extends axially between the first end and a third end, the third end being disposed axially between the first end and the second end.

17 . The gas turbine engine as defined in claim 9 , wherein the coolant is solid at ambient temperature.

18 . A method of cooling a seal runner exposed to a temperature gradient, the method comprising:
providing a coolant in an annular sealed cavity of the seal runner, the coolant being liquid at least at temperatures corresponding to the temperature gradient; and inducing recirculation of the coolant in the sealed cavity, the recirculation being a combined resultant of centrifugal loads caused by a rotation of the seal runner about a central axial axis thereof and of variations in a density of the coolant across the temperature gradient.

19 . The method as defined in claim 18 , wherein the temperature gradient is axial and the coolant is recirculated axially.

20 . The method as defined in claim 18 , wherein the cavity includes a main cavity portion and an auxiliary cavity portion being disposed radially inwardly from the main cavity portion, the auxiliary cavity portion having an axial length shorter than an axial length of the main cavity portion, and inducing recirculation of the coolant includes increasing a density of the coolant in the auxiliary cavity portion through contact with a coolest side of the temperature gradient, circulating the coolant with increased density radially outwardly and axially out of the auxiliary cavity portion, lowering a density of the coolant in the main cavity portion through contact with a hottest side of the temperature gradient, and circulating the coolant with lowered density radially inwardly and into the auxiliary cavity portion.

Assignees

• Pratt & Whitney Canada

Inventors

• Huppe Roger
• Caron Jean-Francois

Classifications

• F16J15/162

  Special parts or details relating to lubrication or cooling of the sealing itself (F16J15/324, F16J15/3404, F16J15/40 take precedence) · CPC title

• F01D11/003 Primary

  by packing rings; Mechanical seals · CPC title

• F05D2240/55

  Seals · CPC title

• F01D25/12

  Cooling · CPC title

• F05D2220/32

  in gas turbines · CPC title