Deaerator for aircraft engine and associated method of operation

Patent metadata

Field	Value
Publication number	US-12017157-B2
Application number	US-202117155895-A
Country	US
Kind code	B2
Filing date	Jan 22, 2021
Priority date	Jan 22, 2021
Publication date	Jun 25, 2024
Grant date	Jun 25, 2024

Abstract

The de-aerator can be used to separate air from oil in an aircraft engine lubrication system. The de-aerator can include a swirler cavity extending circumferentially around axis and axially between a proximal wall and a distal wall, a separation path dividing within the swirler cavity into a radially outer oil segment leading to an oil outlet and a radially inner air segment leading to an air outlet, and a swirling conduit portion having a length turning around the axis upstream of an opening in the proximal wall along the separation path.

First claim

The invention claimed is:

1. A deaerator for an aircraft engine lubrication system, the deaerator comprising:
a swirler cavity extending circumferentially around an axis and axially between a proximal wall and a distal wall,
a separation path dividing the swirler cavity into a radially outer oil segment leading to an oil outlet and a radially inner air segment leading to an air outlet, and
a swirling conduit portion having a length turning around the axis upstream of an opening in the proximal wall along the separation path, the opening fluidly connecting the swirling conduit portion to the swirler cavity, the swirling conduit portion disposed both circumferentially and axially immediately upstream of the opening;
wherein at least a portion of the swirler cavity is provided in the form of a rotor including radially and axially oriented impeller blades, the swirling conduit portion forming part of a stator.

2. The deaerator of claim 1 wherein the opening is crescent-shaped having a curvilinear length oriented circumferentially relative to the axis.

3. The deaerator of claim 2 wherein the opening spans along an angle of at least 45° around the axis.

4. The deaerator of claim 1 wherein the swirling conduit portion turns around the axis along an angle of at least 40°.

5. The deaerator of claim 1 wherein the swirling conduit portion turns around the axis along an angle of at least 55°, upstream of the opening.

6. The deaerator of claim 1 wherein the swirling conduit portion has a cross-sectional shape having an axial dimension and a radial dimension, the axial dimension being constant along more than half the length of the swirling conduit portion, and a pitch of between 0.5 and 1.5 of the axial dimension.

7. The deaerator of claim 6 wherein the pitch is of between 0.8 and 1.2 of the axial dimension.

8. The deaerator of claim 1 wherein a radial distance between a radial center of the opening and the axis is of between 115% and 100% of a radius of curvature of the swirling conduit portion upstream of the opening.

9. The deaerator of claim 8 wherein the radial distance is of between 105 and 110% of the radius of curvature.

10. The deaerator of claim 1 wherein the swirling conduit portion is helical in shape.

11. The deaerator of claim 1 wherein the swirling conduit portion has a radially outer surface and a radially inner surface, the radially outer surface sloping towards the radially inner surface and towards a side adjacent the opening.

12. The deaerator of claim 11 wherein the sloping increases along the length of the swirling conduit portion towards the opening and is configured to fan a flow of concentrated oil radially outwardly towards the radially outer oil segment of the separation path.

13. The deaerator of claim 1 configured for a tangential, angular velocity of fluid exiting the opening to be of between 95% and 110% of an angular velocity of rotation of the impeller blades.

14. The deaerator of claim 1 wherein the separation path extends across an elbow conduit portion upstream of the swirling conduit portion.

15. The deaerator of claim 14 wherein the separation path extends across a straight conduit portion between the elbow conduit portion and the swirling conduit portion.

16. A fluid separator for separating a higher density liquid from a lower density fluid, the separator comprising:
a separation path extending sequentially across a swirling conduit portion and a swirler cavity,
the swirler cavity having an axis and defined within a radially-outer wall, a proximal wall and a distal wall, the proximal wall and the distal wall extending radially inwardly at axially opposite ends of the radially-outer wall,
the separation path dividing within the swirler cavity into a radially outer oil segment leading to an oil outlet and a radially inner air segment leading to an air outlet,
the swirling conduit portion turning around the axis upstream of an opening in the proximal wall, the opening fluidly connecting the swirling conduit portion to the swirler cavity, the swirling conduit portion oriented both circumferentially and axially immediately upstream of the opening;
wherein at least a portion of the swirler cavity is provided in the form of a rotor including radially and axially oriented impeller blades, the swirling conduit portion forming part of a stator.

17. A method of separating air from oil in an aircraft engine lubrication system by using the deaerator recited in claim 1 , the method comprising:
performing a first separation step including conveying a mixture of said air and oil along a swirling conduit portion including turning a flow of the mixture along an axis while simultaneously advancing the flow of the mixture along the axis, said turning causing the oil to concentrate radially outwardly and said air to migrate radially inwardly;
outputting the mixture of air and oil from the swirling conduit portion both circumferentially and axially into a swirler cavity, and performing a second separation step including rotating the mixture of air and oil within the swirler cavity, including directing a radially outward concentration of oil to an oil outlet and a radially inward concentration of air to an air outlet.

18. The method of claim 17 wherein said performing the second separation step includes rotating an impeller within the swirler cavity.

19. The method of claim 17 wherein said outputting the mixture includes outputting the mixture at a circumferential velocity of between 95% and 110% of an angular velocity of the rotating impeller.

Assignees

• Pratt & Whitney Canada

Inventors

• Caron Jean-Francois
• Paradiso Ivan Sidorovich

Classifications

• F02C7/06

  Arrangements of bearings (bearings F16C); Lubricating ({of turbo machines F01D25/18; of machines or} engines in general F01M) · CPC title

• F01D25/20

  using lubrication pumps · CPC title

• F01M2011/038

  comprising lubricant-air separators · CPC title

• F01M11/03

  Mounting or connecting of lubricant purifying means relative to the machine or engine; Details of lubricant purifying means (filters B01D) · CPC title

• F16N2210/08

  Aircraft · CPC title