Patent Application
20240376836
The present disclosure relates generally to machine components requiring removal of lubricant, and more specifically to systems and methods of removing lubricant from the machine components during operating conditions.
Turbine engines are used in a wide variety of power and propulsion applications. An oil sump is an enclosed cavity in a turbine engine where lubricant-wetted components will reside to receive the requisite cooling and lubrication. The oil sump scavenges lubricant via gravity or through a suction pump (“scavenge pump”), or through a combination of gravity and a suction pump. Suction pumps pull an air/oil mix from an oil sump to deliver the return oil for filtering, cooling, and re-use of the oil. When suction pumps are exposed to open air in an oil sump, the pump sucks air and does not pull any meaningful amount of lubricant through the pump.
On some applications of gas turbine engines, there may be severe attitude requirements that the engine must operate such that the gas turbine engine is not level or horizontal with the earth's surface. Such attitude requirements may be pitch and roll requirements, and may increase the difficulty of scavenging lubricant in an oil sump. When a gas turbine engine is not level, lubricant may pool away from a drainage outlet connected to a suction pump or submerge only one drainage outlet while another drainage outlet is open to air in the oil sump.
Conventionally, each drainage outlet has been accompanied by a dedicated suction pump element. The numerous suction pump elements add weight to gas turbine engines and scavenge pumps and increase costs associated with the additional parts, materials, cast housings, and external tubes required for gas turbine engines. Accordingly, there remains a need for further contributions in this area of technology.
The present disclosure may be better understood with reference to the following drawings and description. The components in the figures are not necessarily to scale. Moreover, in the figures, like-referenced numerals designate corresponding parts throughout the different views.
The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.
According to an example, the present disclosure provides an oil sump system for a gas turbine engine. The oil sump system includes a first oil drainage outlet in a surface of the oil sump. The oil sump system further includes a second oil drainage outlet in the surface, the second oil drainage outlet in liquid communication with the first oil drainage outlet. The oil sump system further includes a suction pump in liquid communication with the first oil drainage outlet and the second oil drainage outlet. The oil sump system further includes a valve positioned at the first oil drainage outlet to selectively open and evacuate liquid from the oil sump through the first oil drainage outlet in response to the valve being submerged in liquid, the liquid accumulating on the surface when the gas turbine engine is at level flight.
An interesting feature of the systems and methods described below may be to remove a need for an equal number of drainage outlets and suction pumps, and the reduced number of suction pumps may reduce the weight of a scavenge system significantly, for example by 25% to 35%. Alternatively, or in addition, an interesting feature of the apparatuses and methods described below may be that the cost of a scavenge system is reduced by a reduction in the number of required parts and/or a reduction in materials. Alternatively, or in addition, an interesting feature of the apparatuses and methods described below may be that the cost and weight of the scavenge system is reduced by a reduction in the cost and weight of required cast housings and external tubes.
For purposes of promoting an understanding of the principles of the disclosure, reference will now be made to the examples illustrated in the drawings, and specific language may be used to describe the same. It will nonetheless be understood that no limitation of the scope of the disclosure is intended by the illustration and description of certain examples of the disclosure. In addition, any alternations and/or modifications of the illustrated and/or described example(s) are contemplated as being within the scope of the present disclosure. Further, any other applications of the principles of the disclosure, as illustrated and/or described herein, as would normally occur to one skilled in the art to which the disclosure pertains, are contemplated as being within the scope of the present disclosure.
Referring to
Referring to
Referring to
Valves are located at first drainage outlet 316 and second drainage outlet 318, and may include valves 326, 330 respectively. First drainage outlet 316 is forward of second drainage outlet 318. Examples of valves 326, 330 may include float valves. In other examples, the valves may be ball float valves, gate valves, or valves including actuated control flow, such as electrically or pneumatically by a controller, to move between an open position that allows the flow of liquid 314 and a closed position that does not allow the flow of liquid 314. In the example illustrated in
First drainage outlet 316 is in liquid communication with second drainage outlet 318 at junction point 320. Junction point 320 is in liquid communication with suction pump 324 by scavenge conduit 322. By connecting first drainage outlet 316 and second drainage outlet 318 to suction pump 324, only the single suction pump 324 is required to remove oil through both, or either, first drainage outlet 316 and second drainage outlet 318. In other examples, any number of drainage outlets greater than two are possible.
Liquid 314 submerges both first drainage outlet 316 and second drainage outlet 318 when the gas turbine engine is operating at level flight, as illustrated in
Referring to
Referring to
First drainage outlet 516 and second drainage outlet 520 include valves 512 and 532, respectively, but third drainage outlet 518 does not include a valve. Valves 512, 532 include spherical elements 528, 530, respectively. First drainage outlet 516 and second drainage outlet 520 are not submerged in liquid 514 at the un-level flight orientation illustrated in
First drainage outlet 516, second drainage outlet 520, and third drainage outlet 518 are each in liquid communication with scavenge conduit 524. In the example illustrated in
In a condition in which cavity 502 includes no liquid, such as at startup of the gas turbine engine, suction pump 526 would pull a vacuum such that significant upward pressure may be required on spherical elements 528, 530 for liquid to flow through first drainage outlet 516 or second drainage outlet 520. At least to avoid such a startup vacuum scenario, a valve is not included in at least third drainage outlet 518.
Referring to
Valve 618 is located at first drainage outlet 612. Valve 618 includes spherical element 620. Spherical element 620, which is advantageously fabricated from material that is buoyant in liquid 614, rises to the top of the housing of valve 618, thereby opening valve 618 for evacuation of liquid from cavity 602 through first drainage outlet 612.
First drainage outlet 612 is in fluid communication with second drainage outlet 616 at junction point 622. Junction point 622 is in fluid communication with suction pump 626 by scavenge conduit 624. When first drainage outlet 612 is submerged in liquid 614 at the un-level flight orientation illustrated in
Referring to
Referring to
By adding valves to at least some drainage outlets, the drainage outlets can be fluidically connected together and the drainage outlets can be fluidically connected to a single suction pump. Valves selectively and advantageously close unless submerged in fluid, and the single suction pump will not be able to pull air through a drainage outlet that is not submerged in fluid.
The present disclosure also provides methods for reducing suction of air from an enclosure of a cavity of a gas turbine engine. In an example, a method includes: blocking flow out of the enclosure through a first drainage outlet in a surface of the enclosure; and selectively evacuating fluid from the enclosure through the first drainage outlet in response to an accumulation of fluid at the first drainage outlet. In certain examples, the selectively evacuating may include: accumulating fluid at the first drainage outlet when the gas turbine engine is oriented in a non-horizontal orientation; and evacuating fluid through the first drainage outlet. In other examples, the accumulating may include: raising a float of a float valve in the fluid at the first drainage outlet; wherein the float is buoyant in the fluid.
In certain examples, the surface may include a second drainage outlet fluidically connected to the first drainage outlet; wherein fluid does not accumulate at the second drainage outlet when the gas turbine engine is oriented in the non-horizontal orientation.
In other examples, the method may further include blocking flow out of the enclosure through the second drainage outlet. In still other examples, the blocking may include sealing a second float valve at the second drainage outlet; wherein a second float is resting in the housing of the second float valve under gravity or suction.
The term “aft,” as used herein, unless stated otherwise, alone or in combination with other terms, refers to an element, surface, or assembly being situated at, near, or toward a tail of an aircraft or other vehicle. The term “aft” may be distinguished from the term “forward,” which, as used herein, unless stated otherwise, alone or in combination with other terms, refers to an element, surface, or assembly being situated at, near, or toward a front of an aircraft or other vehicle. The forward and aft directions may refer to opposite directions along an axis, which may be parallel to, or identical to, a centerline of a gas turbine engine. The terms “axial” and “axially,” as used herein, unless stated otherwise, alone or in combination with other terms, refers to elements, surfaces, and assemblies along a common axis, which may be forward or aft relative to other elements, surfaces, and/or assemblies.
A gas turbine engine may be annular. The terms “radially” and “radial,” as used herein, unless stated otherwise, alone or in combination with other terms, refer to elements, surfaces, or assemblies relative to one another along a radius that may project perpendicularly from a centerline axis, which may be parallel to, or identical to, a centerline of a gas turbine engine and/or a forward-aft axis. The terms “inward” and “inwardly,” as used herein, unless stated otherwise, alone or in combination with other terms, refer to an element, surface, or assembly being situated at, near, or toward the centerline axis along a radius. The terms “outward” and “outwardly,” as used herein, unless stated otherwise, alone or in combination with other terms, refers to an element, surface, or assembly being situated, or facing away from, the centerline axis along a radius. The terms “inward” and “inwardly” and the terms “outward” and “outwardly” may refer to opposite directions along a radius projecting perpendicularly from the centerline axis.
The terms “circumferential” and “circumferentially,” as used herein, unless stated otherwise, alone or in combination with other terms, refer to elements, surfaces, or assemblies relative to one another encircling a centerline axis at a radius. Alternatively, or in addition, the terms “circumferential” and “circumferentially,” as used herein, unless stated otherwise, alone or in combination with other terms, mean relating to a circumference of a circle centered on, and perpendicular to, a centerline axis.
The term “fluidically connected” refers to an attachment together of components or elements along a sealed path so as to allow a fluid to flow between the components or elements along the sealed path without inadvertent leakage of the fluid at any attachment point between components or elements.
The terms “horizontal” and “level” refer to a flight orientation in which an aircraft, or a component thereof, is substantially parallel to the surface of the earth. The terms “non-horizontal” and “un-level” refer to a flight orientation in which an aircraft, or a component thereof, is not substantially parallel to the surface of the earth.
For the purpose of this disclosure, the terms “about” and “substantially” are used herein with respect to measurable values and ranges due to expected variations known to those skilled in the art (for example, limitations and variability in measurements).
In describing elements of the present disclosure, the ordinal number terms “1st” “2nd,” “first,” “second,” and the like, may be used herein. These ordinal number terms are only used to distinguish one element from another element, but do not limit the corresponding elements irrespective of the nature or order of the corresponding elements.
All methods and operations described herein may be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context.
The uses of the terms “a” and “an” and “the” and similar referents in the context of describing the present disclosure (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The use of the term “plurality of” is defined by the Applicant in the broadest sense, superseding any other implied definitions or limitations hereinbefore or hereinafter unless expressly asserted by Applicant to the contrary, to mean a quantity of more than one.
As used herein the terms “comprise(s),” “include(s),” “having,” “has,” “can,” “contain(s),” and variants thereof, are intended to be open-ended transitional phrases, terms, or words that do not preclude the possibility of additional acts or structures. The present description also contemplates other examples “comprising,” “consisting,” and “consisting essentially of,” the examples or elements presented herein, whether explicitly set forth or not.
While various examples have been described, it will be apparent to those of ordinary skill in the art that many more implementations are possible. Accordingly, the examples described herein are not the only possible implementations.
The subject-matter of the disclosure may also relate, among others, to the following aspects:
A first aspect relates to an oil sump system for a gas turbine engine, the oil sump system comprising: a first oil drainage outlet in a surface of the oil sump; a second oil drainage outlet in the surface, the second oil drainage outlet in liquid communication with the first oil drainage outlet; a suction pump in liquid communication with the first oil drainage outlet and the second oil drainage outlet; and a valve positioned at the first oil drainage outlet to selectively open and evacuate liquid from the oil sump through the first oil drainage outlet in response to the valve being submerged in liquid, the liquid accumulating on the surface when the gas turbine engine is at level flight.
A second aspect relates to the oil sump system of aspect 1, wherein the valve is a float valve.
A third aspect relates to the oil sump system of aspect 2, wherein a float of the float valve is buoyant in the liquid.
A fourth aspect relates to the oil sump system of any preceding aspect, wherein the liquid is a lubricant.
A fifth aspect relates to the oil sump system of any preceding aspect, further comprising a second valve positioned at the second oil drainage outlet to selectively open and evacuate fluid from the oil sump through the second oil drainage outlet in response to the second valve being submerged in liquid.
A sixth aspect relates to the oil sump system of any preceding aspect, comprising a third oil drainage outlet in the surface, the third oil drainage outlet in liquid communication with the first oil drainage outlet and the second oil drainage outlet.
A seventh aspect relates to the oil sump system of aspect 6, wherein the third oil drainage outlet is positioned at a location in the surface of the oil sump that is farther from the suction pump along a scavenge conduit in fluid communication with the suction pump and the third oil drainage outlet than the first oil drainage outlet and the second oil drainage outlet, the first oil drainage outlet and the second oil drainage outlet in fluid communication with the suction pump by the scavenge conduit.
An eighth aspect relates to the oil sump system of any preceding aspect, wherein the first oil drainage outlet is positioned at a location in the surface of the oil sump that is closer to the suction pump along a scavenge conduit in fluid communication with the suction pump and the first oil drainage conduit, the first oil drainage outlet and the second oil drainage outlet in fluid communication with the suction pump by the scavenge conduit.
A ninth aspect relates to a scavenge system for a gas turbine engine, the scavenge system comprising: a first drainage outlet in a surface of an enclosure of a cavity in the gas turbine engine; a second drainage outlet in the surface, the second drainage outlet in liquid communication with the first drainage outlet; a suction pump in liquid communication with the first drainage outlet and the second drainage outlet; and a valve positioned at the first drainage outlet to selectively open and evacuate liquid from the cavity through the first drainage outlet in response to the valve being submerged in liquid, the liquid accumulating on the surface when the gas turbine engine is at level flight.
A tenth aspect relates to the scavenge system of aspect 9, wherein the valve is a float valve.
An eleventh aspect relates to the scavenge system of aspect 9 or 10, wherein the liquid is a lubricant.
A twelfth aspect relates to the scavenge system of any one of aspects 9 to 11, further comprising a second valve positioned at the second drainage outlet to selectively open and evacuate liquid from the cavity through the second drainage outlet in response to the second valve being submerged in liquid.
A thirteenth aspect relates to the scavenge system of any one of aspects 9 to 12, comprising a third drainage outlet in the surface, the third drainage outlet in liquid communication with the first drainage outlet and the second drainage outlet.
A fourteenth aspect relates to the scavenge system of any one of aspects 9 to 13, wherein the first oil drainage outlet is positioned at a location in the surface of the enclosure that is closer to the suction pump along a scavenge conduit in fluid communication with the suction pump and the first oil drainage conduit, the first oil drainage outlet and the second oil drainage outlet in fluid communication with the suction pump by the scavenge conduit.
A fifteenth aspect relates to a method of reducing suction of air from an enclosure of a cavity of a gas turbine engine, the method comprising: blocking flow of air out of the enclosure through a first drainage outlet in a surface of the enclosure; and selectively evacuating liquid from the enclosure through the first drainage outlet in response to an accumulation of the liquid at the first drainage outlet, the liquid accumulating on the surface when the gas turbine engine is operating at level flight.
A sixteenth aspect relates to the method of aspect 15, wherein the selectively evacuating comprises: accumulating the liquid at the first drainage outlet when the gas turbine engine is oriented in a non-horizontal orientation; and evacuating the liquid through the first drainage outlet.
A seventeenth aspect relates to the method of aspect 16, wherein the accumulating comprises: raising a float of a float valve in the liquid at the first drainage outlet; wherein the float is buoyant in the liquid.
An eighteenth aspect relates to the method of aspect 16 or 17, wherein the surface comprises a second drainage outlet, the second drainage outlet in liquid communication with the first drainage outlet; and wherein the liquid does not accumulate at the second drainage outlet when the gas turbine engine is oriented in the non-horizontal orientation.
A nineteenth aspect relates to the method of aspect 18, wherein the method further comprises: blocking flow of air out of the enclosure through the second drainage outlet.
A twentieth aspect relates to the method of aspect 19, wherein the blocking comprises: sealing a second float valve at the second drainage outlet; wherein a second float is resting in a seat of the second float valve under gravity or suction.
In addition to the features mentioned in each of the independent aspects enumerated above, some examples may show, alone or in combination, the optional features mentioned in the dependent aspects and/or as disclosed in the description above and shown in the figures.
