Oil drainback assembly for a bearing compartment of a gas turbine engine
A bearing compartment of a gas turbine engine includes a rotationally fixed structure defined about an engine longitudinal axis; a gutter section formed in the front support; an oil drainback assembly mountable to the gutter section to direct oil into a drain passage to communicate oil from the gutter.
1. An oil drainback assembly for a bearing compartment of a gas turbine engine comprising:
a shaft with a threaded section along an axis, and an oil distribution passage transverse to the axis;
a head transverse to the threaded section, and a drain passage that extends through the head and into communication with the oil distribution passage;
a windage blocker that extends from the head;
a nut receivable onto the threaded section; and
a directional fitting receivable onto the shaft and retained by the nut.
2. The assembly as recited in claim 1 , wherein the windage blocker includes a first wall and a second wall that flank the drain passage on the head.
3. The assembly as recited in claim 2 , wherein the first wall is offset from the second wall.
4. The assembly as recited in claim 1 , wherein the directional fitting forms an annulus around the shaft.
5. The assembly as recited in claim 4 , wherein the directional fitting forms an oil outlet passage from the annulus.
6. A bearing compartment of a gas turbine engine comprising:
a rotationally fixed structure defined about an engine longitudinal axis;
a gutter section formed in the front support; and
an oil drainback assembly mountable to the gutter section to direct oil into a drain passage to communicate oil from the gutter, wherein the oil drainback assembly comprises:
a shaft with a threaded section along an axis, and an oil distribution passage transverse to the axis;
a head transverse to the threaded section, and a drain passage that extends through the head and into communication with the oil distribution passage; and
a windage blocker that extends from the head, wherein the oil drainback assembly is mountable to the gutter section via a nut, and further comprising a directional fitting retained by the nut.
7. The bearing compartment as recited in claim 6 , wherein the rotationally fixed structure is a front support structure that extends forward of a seal assembly of the bearing compartment.
8. The bearing compartment as recited in claim 7 , further comprising a rotating slinger mounted to the seal assembly, the rotating slinger inboard of the gutter section with respect to the engine longitudinal axis.
9. The bearing compartment as recited in claim 6 , wherein the rotationally fixed structure at least partially separates an oil-wetted zone from a non-oil-wetted zone in the bearing compartment.
10. The bearing compartment as recited in claim 6 , wherein the oil drainback assembly is mountable to the gutter section through an aperture formed in the gutter section at bottom dead center.
11. The bearing compartment as recited in claim 6 , wherein the directional fitting directs oil into an oil-wetted zone.
12. A method for capturing wept oil in a bearing compartment of a gas turbine engine comprising:
forming an aperture in a gutter section of a rotationally fixed structure defined about an engine longitudinal axis, the rotationally fixed structure at least partially separates an oil-wetted zone from a non-oil-wetted zone in the bearing compartment; and
mounting an oil drainback assembly in the aperture to direct wept oil from a seal assembly through oil drainback assembly and into the oil-wetted zone, wherein the oil drainback assembly comprises:
a shaft with a threaded section along an axis, and an oil distribution passage transverse to the axis;
a head transverse to the threaded section, and a drain passage that extends through the head and into communication with the oil distribution passage; and
a windage blocker that extends from the head, wherein the oil drainback assembly further comprises a nut receivable onto the threaded section and a directional fitting retained by the nut.
13. The method as recited in claim 12 , further comprising creating both a calming area for oil to pool and build head pressure for the oil to drain down the drain passage as well as a pumping action due to the direction of rotation of the recirculation zone.
14. The method as recited in claim 12 , further comprising changing an oil concentration circumferentially around the gutter section due to the presence of the windage blocker.