Gas turbine engine oil flow control system

Abstract

A gas turbine engine oil flow control system may include a variable flow oil pump that may be used to provide oil to various oil consumers (e.g., power gearboxes, engine shaft bearings, generators, etc.) at different rates. An oil flow control valve having a capability to provide variable oil flow may be used in conjunction with a variable flow oil pump. A flow sensor may be used with an oil flow controller to measure oil flow at various points in a gas turbine engine oil flow control system. The oil flow controller may use information from the flow sensor and a variable consumption demand associated with one or more oil consumers (provided to the oil controller or calculated based on the operating demand of the oil consumers) to vary the operation of the variable flow oil pump and / or oil flow control valve.

Description

Technical Field

[0001] The present disclosure relates to oil flow control systems used in gas turbine engines. Background Art

[0002] A gas turbine engine typically includes a fan and a core arranged to flow in communication with each other. The core of a gas turbine engine typically includes a compressor section, a combustion section, a turbine section, and an exhaust section in a series flow order. In operation, at least a portion of the air above the fan is provided to the inlet of the core. This portion of air is gradually compressed by the compressor section until it reaches the combustion section. Fuel is mixed with the compressed air and burned in the combustion section to provide combustion gases. The combustion gases are directed from the combustion section through the turbine section to drive one or more turbines in the turbine section. One or more turbines in the turbine section may be coupled to one or more compressors of the compressor section via corresponding shafts. The combustion gases are then directed to, for example, the atmosphere through the exhaust section.

[0003] Thus, a gas turbine engine includes various rotating parts that are typically provided with some form of oil for use by one or more oil consumers that require the use of oil. For example, a gas turbine engine includes one or more bearings for supporting the rotation of a shaft that connects a turbine section to a compressor section. A generator may be used with a gas turbine engine and may use oil as a coolant. Providing oil to various oil consumers at a reliable flow rate remains an area of ​​interest. It would be useful in the art to improve the supply of oil to various oil consumers associated with gas turbine engine operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0004] A complete and enabling disclosure of the presently described technology, including the best mode thereof, to one of ordinary skill in the art is set forth in the specification with reference to the accompanying drawings, in which:

[0005] Figure 1 is a schematic cross-sectional view of a gas turbine engine according to an exemplary aspect of the present disclosure.

[0006] Figure 2 is a cross-sectional view of a portion of a gas turbine engine according to another exemplary embodiment of the present disclosure.

[0007] Figure 3 is a schematic diagram of an oil flow control system according to an exemplary embodiment of the present disclosure.

[0008] Figure 4 is a schematic diagram of an oil flow control system according to another exemplary embodiment of the present disclosure.

[0009] Figure 5 is a schematic diagram of an oil flow controller according to another exemplary embodiment of the present disclosure.

[0010] Figure 6 is a schematic diagram of a computing device according to another exemplary embodiment of the present disclosure.

[0011] Figure 7 is a description of a method of operating a gas turbine engine oil flow control system according to another exemplary embodiment of the present disclosure. DETAILED DESCRIPTION

[0012] Reference will now be made in detail to the present embodiments of the present disclosure, one or more examples of which are illustrated in the accompanying drawings. The detailed description uses numerical and letter designations to refer to features in the drawings. Like or similar designations in the drawings and description have been used to refer to like or similar parts of the present disclosure.

[0013] As used herein, the word "exemplary" means "serving as an example, instance, or illustration." Any implementation described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other implementations. In addition, unless expressly stated otherwise, all embodiments described herein should be considered exemplary.

[0014] The singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise.

[0015] The term “turbomachine” refers to a machine that includes one or more compressors, a heat generating section (eg, a combustion section), and one or more turbines that together produce a torque output.

[0016] The term "gas turbine engine" refers to an engine having a turbine as all or part of its power source. Example gas turbine engines include gas turbine engines, turboprop engines, turbojets, turboshaft engines, etc., as well as hybrid electric versions of one or more of these engines.

[0017] The term "combustion section" refers to any heat addition system of a turbomachine. For example, the term combustion section may refer to a section that includes one or more of a deflagration combustion assembly, a rotating detonation combustion assembly, a pulse detonation combustion assembly, or other suitable heat addition assemblies. In certain example embodiments, the combustion section may include an annular combustor, a can combustor, a tubular combustor, a trapped vortex combustor (TVC), or other suitable combustion systems, or combinations thereof.

[0018] The terms "axial" and "axially" refer to directions and orientations extending substantially parallel to a reference axis. Additionally, the terms "radial" and "radially" refer to directions and orientations extending substantially perpendicular to a reference axis. Additionally, as used herein, the terms "circumferential" and "circumferentially" refer to directions and orientations extending in an arc around a reference axis.

[0019] Unless otherwise specified herein, the terms "coupled," "fixed," "attached to," and the like refer to both direct coupling, fixing, or attachment as well as indirect coupling, fixing, or attachment through one or more intermediate components or features.

[0020] As used herein, the terms “first,” “second,” and “third” may be used interchangeably to distinguish one component from another, and are not intended to indicate the position or importance of each component.

[0021] The present disclosure generally relates to systems and methods for controlling oil flow used with oil consumers associated with the operation of a gas turbine engine. During operation of the gas turbine engine, one or more oil consumers (e.g., a power gearbox or an electric motor) may require a change in lubrication (e.g., in a power gearbox) or a change in cooling (e.g., in an electric motor, where oil may be used as a heat exchange medium). A variable flow oil pump powered by a gas turbine engine or any other suitable power source may be used to provide a variable oil flow for use by one or more oil consumers. The variable flow oil pump may be electrically driven (e.g., via an external power source (e.g., a battery), or electrically driven by a generator driven by the gas turbine engine) or mechanically driven (e.g., via a shaft driven by the gas turbine engine). In addition, an oil flow control valve may also be used to ensure that an appropriate amount of oil is delivered to the associated oil consumer. An oil flow controller may be used to coordinate the operation of the variable flow oil pump and the oil flow control valve. The oil flow controller may change the variable flow oil pump and / or the oil flow control valve based on the variable consumption requirements associated with the oil consumer, the oil consumer being associated with the oil flow control valve. The oil flow controller may also use additional information, such as flow rate data generated from a flow rate sensor and / or flow data from a flow data sensor (e.g., a sensor measuring pressure and / or temperature) to help control the variable flow oil pump and / or the oil flow control valve. Such flow rate data will be understood to include a single data point or multiple data points indicating the rate of oil, as will be further described below.

[0022] Referring now to the drawings, wherein like numerals refer to like elements throughout the several views, Figure 1 is a schematic cross-sectional view of a gas turbine engine 10 according to an exemplary embodiment of the present disclosure. More specifically, Figure 1 In the embodiment of the present invention, the gas turbine engine 10 is in the form of a high bypass turbofan jet engine, referred to herein as a "turbofan engine". In other embodiments, the gas turbine engine 10 may take other forms, such as, but not limited to, a turbojet engine, a turboprop engine, and a turboshaft engine. Reference to a turbofan engine is not intended to be limiting. Figure 1As shown, the gas turbine engine 10 defines an axial direction A (extending parallel to a longitudinal centerline 12 provided for reference) and a radial direction R. Generally, the turbofan 10 includes a fan section 14 and a core turbine engine 16 disposed downstream of the fan section 14 .

[0023] The illustrated exemplary core turbine engine 16 generally includes a substantially tubular outer casing 18 defining an annular inlet 20. In addition, the exemplary core turbine engine 16 includes, in series flow relationship, and the outer casing 18 surrounds, in series flow relationship, a compressor section including a supercharger or low pressure (LP) compressor 22 and a high pressure (HP) compressor 24; a combustion section 26; a turbine section including a high pressure (HP) turbine 28 and a low pressure (LP) turbine 30; and an ejection exhaust nozzle section 32. A high pressure (HP) shaft or spool 34 drivingly connects the HP turbine 28 to the HP compressor 24. A low pressure (LP) shaft or spool 36 drivingly connects the LP turbine 30 to the LP compressor 22. The compressor section, combustion section 26, turbine section, and nozzle section 32 together define a core air flow path 37.

[0024] For the illustrated embodiment, the fan section 14 includes a variable pitch fan 38 having a plurality of fan blades 40 that are coupled to a disk 42 in a spaced manner. Not all embodiments need include a variable pitch fan 38. As shown, the fan blades 40 extend outwardly from the disk 42 generally in a radial direction R. Each fan blade 40 is capable of rotating relative to the disk 42 about a pitch axis P by means of the fan blades 40 being operably coupled to a suitable pitch changing mechanism 44, which is configured to change the pitch of the fan blades 40 in unison. The fan blades 40, the disk 42, and the pitch changing mechanism 44 are capable of rotating together about the longitudinal axis 12 through the LP shaft 36 across the power gearbox 46. The power gearbox 46 includes a plurality of gears for adjusting the rotational speed of the fan 38 relative to the LP shaft 36 to a more efficient fan speed.

[0025] Still refer to Figure 1 In the exemplary embodiment of the present invention, the disk 42 is covered by a rotatable front hub 48 having an aerodynamic profile to facilitate airflow through the plurality of fan blades 40. In addition, the exemplary fan section 14 includes an annular fan case or outer nacelle 50 that circumferentially surrounds the fan 38 and / or at least a portion of the core turbine engine 16. The exemplary nacelle 50 is supported relative to the core turbine engine 16 by a plurality of circumferentially spaced outlet guide vanes 52. In addition, a downstream section 54 of the nacelle 50 extends over an outer portion of the core turbine engine 16, thereby defining a bypass airflow passage 56 therebetween.

[0026] During operation of the gas turbine engine 10, a volume of air 58 enters the turbofan 10 through the nacelle 50 and / or the associated inlet 60 of the fan section 14. As the volume of air 58 passes through the fan blades 40, a first portion of the air 58 (as indicated by arrow 62) is directed or directed into the bypass airflow passage 56, while a second portion of the air 58 (as indicated by arrow 64) is directed or directed into the core air flow path 37, or more specifically, into the LP compressor 22. The ratio between the first portion 62 of air and the second portion 64 of air is generally referred to as the bypass ratio. The pressure of the second portion 64 of air is then increased as it is directed through the high pressure (HP) compressor 24 and into the combustion section 26, where it is mixed with fuel and combusted to provide combustion gases 66.

[0027] The combustion gases 66 are directed through the HP turbine 28, wherein a portion of the heat and / or kinetic energy from the combustion gases 66 is extracted via successive stages of HP turbine stator blades 68 coupled to the outer casing 18 and HP turbine rotor blades 70 coupled to the HP shaft or spool 34, thereby rotating the HP shaft or spool 34 to support operation of the HP compressor 24. The combustion gases 66 are then directed through the LP turbine 30, wherein a second portion of the heat and kinetic energy is extracted from the combustion gases 66 via successive stages of LP turbine stator blades 72 coupled to the outer casing 18 and LP turbine rotor blades 74 coupled to the LP shaft or spool 36, thereby rotating the LP shaft or spool 36 to support operation of the LP compressor 22 and / or rotation of the fan 38.

[0028] The combustion gases 66 are then directed through the jet exhaust nozzle section 32 of the core turbine engine 16 to provide propulsive thrust. At the same time, the pressure of the first portion of the air 62 is significantly increased as it is directed through the bypass airflow passage 56 before being discharged from the fan nozzle exhaust section 76 of the turbine fan 10, also providing propulsive thrust. The HP turbine 28, the LP turbine 30, and the jet exhaust nozzle section 32 at least partially define a hot gas path 78 for directing the combustion gases 66 through the core turbine engine 16.

[0029] Figure 1 The exemplary gas turbine engine 10 shown in is configured as an underwing mounted commercial aircraft engine. Commercial aircraft engines are integrated into taxi aircraft used to transport passengers and / or cargo. For example, government regulations and economic drivers require that commercial aircraft engines emphasize reliability, fuel efficiency, low emissions, etc., rather than power generation and responsiveness, such as military aircraft engines. In addition, Figure 1 The exemplary gas turbine engine 10 shown in FIG. 1 is configured to generate a relatively large amount of thrust. For example, Figure 1The exemplary gas turbine engine 10 shown in FIG. 1 may be configured to produce at least about 14,000 pounds of thrust at takeoff under standard day conditions (e.g., sea level and approximately 60° F.). However, in other exemplary embodiments, the gas turbine engine 10 may alternatively be configured to produce at least about 18,000 pounds of thrust, at least about 20,000 pounds of thrust, at least about 30,000 pounds of thrust, at least about 40,000 pounds of thrust, or more. Notably, because the illustrated gas turbine engine 10 is configured as a commercial aircraft engine, the gas turbine engine 10 may need to produce such thrust more reliably than, for example, a similarly sized military aircraft engine.

[0030] However, it should be understood that Figure 1 The exemplary gas turbine engine 10 shown in FIG. 1 is for example only, and in other exemplary embodiments, the gas turbine engine 10 may have any other suitable configuration. It should also be understood that in other exemplary embodiments, aspects of the present disclosure may be incorporated into any other suitable gas turbine engine. For example, in other exemplary embodiments, aspects of the present disclosure may be incorporated into, for example, a turboprop engine, a turboshaft engine, or a turbojet engine.

[0031] Reference now Figure 2 , provides a schematic cross-sectional view of the aft end of a gas turbine engine 10 according to an exemplary embodiment of the present disclosure. Specifically, Figure 2 The aft end of the core engine 16 of an exemplary gas turbine engine 10 is depicted according to an exemplary embodiment of the present disclosure. In certain exemplary embodiments, Figure 2 The exemplary gas turbine engine 10 may be operated with Figure 1 The exemplary gas turbine engines 10 are configured in substantially the same manner. Therefore, the same or similar numbers may refer to the same or similar parts.

[0032] As shown, the core engine 16 of the illustrated gas turbine engine 10 includes a turbine section having a turbine 80. The turbine 80, in turn, includes a plurality of stages of rotatable rotors 82 attached to corresponding plurality of stages of rotor blades 84—wherein each stage of rotors 82 includes a structural arm 86 that attaches each corresponding stage of rotors 82 to an adjacent stage of rotors 82. Further, as shown, each rotor 82 includes a base 88 that is positioned radially inwardly in a rotor bore 90 defined by the gas turbine engine 10. Further, between each stage of rotor blades 84, the turbine 80 includes a plurality of stator blades 92. A structural frame member 94 is attached to the plurality of stages of rotors 82 and connects the rotors 82 to a shaft 96 such that the shaft 96 is drivingly connected to the turbine 80. In at least some exemplary embodiments, the turbine 80 of the turbine section may be configured as a low pressure turbine (see Figure 1LP turbine 30 in FIG. 1 ), and shaft 96 may be configured as a low pressure shaft (see Figure 1 LP shaft 36 in FIG. 1 ). Thus, for such an exemplary embodiment, shaft 96 may extend forward to the low pressure compressor (see FIG. Figure 1 LP compressor 22), so that turbine 80 drives shaft 96 to rotate and thus rotate the low pressure compressor.

[0033] In addition, the core engine 16 includes a bearing 98 for supporting the rotation of the shaft 96, the structural frame member 94, and the turbine 80. Specifically, the core engine 16 includes a static frame member 100 fixed to the non-rotating part of the core engine 16. In addition, the structural frame member 94 includes an extension 102. The bearing 98 is positioned between the static frame member 100 and the extension 102 of the structural frame member 94, so that the static frame member 100 supports the structural member and the shaft 96 through the bearing 98, for example, axially and radially. The bearing 98 shown is configured as a single roller bearing. However, in other exemplary embodiments, the bearing may also include a plurality of bearings, such as a pair of roller bearings, a ball bearing and a roller bearing, a pair of tapered roller bearings, etc. In addition, in certain exemplary embodiments, the bearing 98 may be formed of a metal material (e.g., stainless steel), or alternatively may be formed of a non-ferrous material (e.g., a ceramic material).

[0034] As shown, the gas turbine engine 10 includes a bearing reservoir 104 disposed in the core engine 16 for containing lubricant in the form of oil provided to the bearing 98, wherein the lubricant is suitable for lubricating the rolling element bearings of the gas turbine engine (e.g., for lubricating the engine shaft bearings associated with either the LP shaft 36 or the HP shaft 34). The bearing reservoir 104 surrounds the bearing 98, defines a bearing reservoir cavity 106, and includes a bearing seal 108 for preventing the lubricant from escaping from the bearing reservoir cavity 106.

[0035] Still refer to Figure 2 In an exemplary embodiment of the present invention, the gas turbine engine 10 additionally includes at most one drain compartment positioned between the sump cavity of the bearing sump 104 and the rotor bore 90 of the core engine 16. Specifically, for the illustrated embodiment, the at most one drain compartment is configured as a main drain compartment 110, which includes a drain seal 112 and defines a main drain cavity 114. As shown, the bearing sump seal 108 separates the bearing sump cavity 106 of the bearing sump 104 from the main drain cavity 114 of the main drain compartment 110. In addition, the drain seal 112 separates the main drain cavity 114 of the main drain compartment 110 from the rotor bore 90. The main drain cavity 114 is configured to capture any lubricant that leaks from the sump cavity seal 108 during operation of the gas turbine engine 10.

[0036] like Figure 2 As shown, the exemplary embodiment also includes a single cooling passage 118, also referred to as a pressurized air cavity. Specifically, the cooling passage 118 is configured to receive a cooling air flow from, for example, a compressor section at an inlet 120, and is also fluidly connected to the cavity 114 of the main drain compartment 110 via an opening 119. Therefore, for the illustrated embodiment, the main drain compartment 110 and the cooling passage 118 are combined. The cooling passage 118 can be used as a thermal barrier between the bearing reservoir cavity 106 and the rotor bore cavity 90. However, it is worth noting that, since the bearing reservoir 104 and the lubricant are capable of operating at relatively high temperatures, no additional barriers or drain compartments are provided on the outside of the bearing reservoir 104 in addition to the cooling passage 118 and the main drain compartment 110, as shown.

[0037] In addition, the gas turbine engine 10 includes a drain line 116 that fluidly connects the main drain cavity 114 to a desired location. For the illustrated embodiment, the drain line 116 fluidly connects the main drain cavity 114 to the core air flow path 37 of the core engine 16 through the opening 119 and the cooling passage 118. As discussed above, the lubricant can be configured as a non-flammable lubricant, so if the lubricant is provided to the core air flow path 37 within the turbine section of the core engine 16, there is no concern that the lubricant will burn. With this configuration, the core engine 16 may not require a dedicated strut extending through the core air flow path 37, otherwise the drain line 116 would extend through the dedicated strut.

[0038] However, it should be appreciated that in other embodiments, the drain line 116 may alternatively fluidly connect the drain cavity 114 to a location radially outside of the core air flow path 37 of the core engine 16, such as to a bypass passage 56 of the gas turbine engine 10, or to an ambient location or any other suitable location. With this configuration, the core engine 16 may include a strut extending through the core air flow path 37 through which the drain line 116 extends to the location. Additionally, while the drain line 116 is depicted as being fluidly connected to the main drain compartment 114 via the opening 119 and the cooling passage 118, in other exemplary embodiments, the drain line 116 may alternatively be fluidly connected directly to the main drain compartment 114.

[0039] Now go to Figure 3, shows an embodiment of an oil flow control system 122 that includes a gas turbine engine 10 that is configured to provide power to a variable flow oil pump 124 during operation of the gas turbine engine 10. The variable flow oil pump 124 can be configured to receive shaft mechanical power directly from the gas turbine engine 10 (e.g., via an offtake shaft driven by either the LP shaft 36 or the HP shaft 34), but other techniques can also be used to provide power. In one non-limiting form, the gas turbine engine 10 can provide mechanical power to a generator for generating electricity. In this form, the variable flow oil pump 124 can be electrically driven and powered by a generator driven by mechanical power from the gas turbine engine 10.

[0040] The variable flow oil pump 124 is used to generate a variable pump oil flow 126, which is delivered to the oil consumer. The oil consumer is associated with the operation of the gas turbine engine 10 and can take the form of any component or system within the gas turbine engine 10 or any accessory that operates in conjunction with the gas turbine engine 10. For example, the oil consumer can be any one of a power gearbox, an engine shaft bearing, a generator, an accessory driven by the engine, etc. The oil consumer can use the oil provided by the variable flow oil pump 124 as a lubricant or a heat exchange fluid, or both. The variable flow oil pump 124 can take any various forms that can be used to generate a variable pump oil flow 126, including an electric drive form with speed control, or a variable displacement form. As shown, before the oil is used by the oil consumer, there is no bypass loop to return the oil to the inlet of the variable flow oil pump 124. The variable flow oil pump 124 is capable of providing oil of various flow rates to the oil consumer. The variable flow oil pump 124 can also provide a rapid response of the flow rate output to changes in the pump control command. The variable flow oil pump 124 can provide a variable flow of oil 126 at various flow rates. For example, the variable flow oil pump 124 can include pumping speeds ranging from no flow rate, maximum flow rate, and partial flow rate. In one non-limiting example, the partial flow rate can include a single partial flow rate, while in another non-limiting example, multiple partial flow rates are contemplated. The variable flow oil pump 124 can include discrete partial flow rates between no flow rate and maximum flow rate, while in other cases, the partial flow rate can be continuously varied between no flow rate and maximum flow rate.

[0041] Figure 3 1 shows that the pump variable oil flow 126 is delivered to two different oil circuit branches, wherein each oil circuit branch delivers oil to a different oil consumer. Figure 3 The embodiment shown in shows two oil circuit branches, but other embodiments may have fewer or more oil circuit branches. As shown in the figure, Figure 3The embodiment also includes a flow rate sensor 128 for sensing the velocity of the oil and generating flow rate data indicative of the velocity of the oil. Since each flow rate sensor 128 in each oil circuit branch can be associated with an oil consumer, and considering the incompressible nature of the oil flowing to the oil consumer, the flow rate data can indicate the velocity of the oil to the oil consumer.

[0042] The oil flow control valve 130 is positioned downstream of the variable flow oil pump 124 and is configured to provide a variable oil flow to an oil consumer (e.g., a power gearbox, an engine shaft bearing, a generator, accessories driven by the engine, etc.). The oil flow control valve 130 can be operated using a torque motor or a stepper motor and is configured to further regulate the oil flow in the oil circuit branch where the oil flow control valve 130 is located. The oil flow control valve 130 can provide a valve variable oil flow 132 at various flow rates to further regulate the oil flow to the oil consumer beyond the regulation range provided by the variable flow oil pump 124. For example, the oil flow control valve can provide a variable oil flow 132 using a range of valve positions from fully closed, fully open, and partially open. In one non-limiting example, the partially open valve position can include a single partially open valve position, while in another non-limiting example, multiple partially open valve positions are contemplated. The oil flow control valve 130 can include discrete partially open valve positions between the fully closed and fully open positions, while in other embodiments, the partially open position can be continuously varied between the fully open and fully closed valve positions. In one form, the valve variable oil flow 132 is lower than the pump variable oil flow 126, for example Figure 3 In the illustrated embodiment, the pump variable oil flow 126 is split between the oil circuit branches. However, it is contemplated that in an embodiment including only one oil circuit branch, the valve variable oil flow 132 is the same as the pump variable oil flow 124. In addition, in one operating mode, the oil flow control valve can be completely closed, thereby making Figure 1 , presented as a single circuit branching embodiment until the oil flow control valve 130 is opened.

[0043] Although the oil flow control valve 130 is depicted as a conventional two-way valve having a single inlet fed from the variable flow oil pump 124 and a single outlet leading to the oil consumers, in some forms, the oil control valve 130 may employ other valve types including, but not limited to, a three-way valve, a four-way valve, etc. In these alternative forms, a flow rate sensor 128 may be used in each of the flow split lines leading to the various oil consumers (or at different locations within a given oil consumer).

[0044] The oil flow control system 122 may also include a flow rate sensor 128 that helps determine the velocity of the oil, which may include a mass flow rate or a volume flow rate of the oil. Figure 3As shown, a flow rate sensor 128 is positioned downstream of an oil flow control valve 130, while another flow rate sensor 128 is positioned downstream of a variable flow oil pump 124, without an oil flow control valve 130 in between. Not all embodiments need include flow rate sensors 128 in all conduits that receive oil from the variable flow oil pump 124. In some forms, a fewer or greater number of flow rate sensors 128 may be used. In addition to the above, a flow rate sensor 128 may be positioned on a return branch from the gas turbine engine 10 to the variable flow oil pump 124. The flow rate sensor 128 on the return branch may be used to determine the rate of oil returning toward the variable flow oil pump 124. Although Figure 3 The embodiment shown in FIG. 1 shows a flow sensor 128 on each oil circuit branch and return branch, but a fewer number of flow sensors 128 may be used. For example, if only oil delivery to oil consumers is desired, then a flow sensor 128 on the return branch to the variable flow oil pump 124 may not be needed. In other embodiments, multiple flow sensors 128 may be included for fault detection purposes and / or fault adaptation purposes.

[0045] The flow rate sensor 128 can determine the mass flow rate or volume flow rate of the oil and can generate flow rate data indicative of the velocity of the oil sensed by the flow rate sensor 128. The flow rate sensor 128 can take a variety of forms including, but not limited to, turbine flow meters and ultrasonic flow meters, to name a few examples.

[0046] The oil flow controller 134 is used in the gas turbine engine oil flow control system 122 to monitor the operation of the gas turbine engine 10 and any oil consumers associated with the operation of the gas turbine engine 10 and to regulate the oil flow to the oil consumers by using the variable flow oil pump 124 and the flow rate sensor 128. The oil flow controller 134 may be integrated into an engine controller (e.g., a full authority digital engine controller (FADEC) or a control unit shown as Figure 1111 in the engine controller 10), or may exist independently and interface with the engine controller. The oil flow controller 134 may be configured to receive and / or determine the variable consumption demand of the oil consumer. For example, the oil flow controller 134 may receive the variable consumption demand from the engine controller based on the operation of the gas turbine engine 10. In some applications, a small change in the speed of the core turbine engine 16 may be converted into a large change in the power flow through the power gearbox 46, which may result in a large change in the oil delivery demand. In such an application, the variable consumption demand from the engine controller may cause a large change in the variable flow oil pump 124 and / or the oil flow control valve 130. In a non-limiting example of the oil flow to the power gearbox 46, the oil flow can be used to lubricate and cool the gears in the power gearbox 46 and the bearings in the power gearbox 46. The oil flow to the gears may be 8.8 gallons per minute (33 liters per minute) at takeoff power, but only 6.4 gallons per minute (24.3 liters per minute) at ground idle. Oil flow to the bearings may be 1.9 gpm (7.1 lpm) at takeoff power, but only 1.4 gpm (5.2 lpm) at ground idle.

[0047] The oil flow controller 134 is configured to receive flow rate data from the flow rate sensor 128 and generate pump control commands to control the variable flow oil pump 124. In some forms, in those embodiments where the oil flow controller 134 is not integrated into the engine controller, the oil flow controller 134 may also receive information (e.g., data, commands, etc.) from the engine controller. The oil flow controller 134 may communicate wired or wirelessly with each of the flow rate sensor 128 and the variable flow oil pump 124. In some forms, a data bus may be used to transmit pump control commands and / or flow rate data.

[0048] The oil flow controller 134 may also receive flow data generated by a flow data sensor 136, which indicates a condition of the oil, such as temperature or pressure. Although only a single flow data sensor 136 is provided, a greater number of flow data sensors 136 may be used in the oil flow control system 122 and may be placed anywhere throughout the gas turbine engine oil flow control system 122. The flow data generated by the flow data sensor 136 may be used to confirm proper delivery of fluid to any given oil consumer associated with the flow data sensor 136 and / or to vary the rate at which oil is delivered to the oil consumer based on the flow data.

[0049] Thus, the oil flow controller 134 can generate a pump control command to provide a pump variable oil flow that will, in aggregate, satisfy each of the oil consumers associated with the operation of the gas turbine engine. Additionally, the oil flow controller 134 can generate a valve command for the oil flow control valve 130 to provide a valve variable oil flow 132 suitable for an oil consumer associated with the circuit branch (222a–222e) associated with the oil flow control valve 130. It is contemplated that the pump variable oil flow will be equal to the sum of all circuit branches associated with the oil consumers, regardless of whether each of the circuit branches includes an oil flow control valve 130. In those branches that do not include an oil flow control valve 130, it is contemplated that the dimensions of these particular branches can be designed to receive various rates of oil, taking into account the regulation of the pump variable oil flow 126 and the valve variable oil flow 132. Further to the above, particularly with respect to the flow data sensor 136 , if an oil consumer (e.g., a generator) requires cooling, but the temperature of the oil measured by the flow data sensor 136 is high for the variable oil flow 132 delivered from the oil flow control valve 130 , the oil flow controller may increase the variable oil flow 132 by increasing the rate provided from the oil flow control valve 130 and / or increasing the pump variable oil flow provided from the variable flow oil pump 124 .

[0050] Now go to Figure 4 , depicts another embodiment of the oil flow control system 122, wherein Figure 3 At least one difference is that oil consumers 138a-138e (collectively, oil consumers 138) associated with the operation of the gas turbine engine 10 are depicted. Figure 3 and Figure 4 Like reference numerals denote like elements. The gas turbine engine 10 is not Figure 4 , but it is concealed, for example by engine shaft bearing 138b. Figure 4 The example oil consumers 138 depicted in the diagram include a power gearbox 138a, an engine shaft bearing 138b, accessories 138c, a generator 138d, and associated other oil consumers 138e (representative of any number of other oil consumers). In addition, although the oil flow controller 134 is not shown, it should be understood that the oil flow control valve 130, the flow rate sensor 128, and the flow data sensor 136 communicate with the oil flow controller 134, as with the embodiments described elsewhere herein. For example, the oil flow controller 134 can generate a valve command to be sent to the oil flow control valve 130, while the flow rate sensor 128 generates flow rate data to be transmitted to the oil flow controller 134. Therefore, Figure 4The illustration in is a simplified view of multiple circuit branches (222a-222e) where it is assumed that an oil flow controller 134 is present, but not shown. In addition, as described above, although each of the circuit branches (222a-222e) leading to the oil consumer 138 is depicted as having an oil flow control valve 130 and a flow rate sensor 128, it should be understood that some embodiments may lack one or both of the oil flow control valve 130 and the flow rate sensor 128 in any given circuit branch leading to the corresponding oil consumer 138.

[0051] The oil flow control system 122 may include an oil tank 140 positioned in the return branch to the variable flow oil pump 124, and a heat exchanger 142 in communication with the outflow end of the variable flow oil pump 124 and prior to being branched into the various loop branches. The oil tank 140 may be used to provide an oil reservoir from which the variable flow oil pump 124 draws its oil source. The oil tank 140 may also serve as a buffer given the incompressible nature of oil and the need to vary the rate at which oil is provided throughout the oil flow control system 122. However, not all embodiments of the oil flow control system 122 include an oil tank 140. Similarly, not all embodiments of the oil flow control system 122 include a heat exchanger 142. In those embodiments that include a heat exchanger 142, for example Figure 4 In the embodiment shown in , a heat exchanger 142 is used to change the temperature of the pump variable oil flow 126. In some forms, the heat exchanger can be an on-demand heat exchanger that is capable of providing variable cooling and / or heating of the oil flowing through the heat exchanger 142. However, in other forms, the heat exchanger 142 is constrained by the nature of its design. The heat exchanger 142 can be an air / oil heat exchanger or a fuel / oil heat exchanger to meet the needs of any given application.

[0052] Now go to Figure 5, shows an embodiment of an oil flow controller 134 in communication with a flow rate sensor 128 and a flow data sensor 136, each of which transmits flow rate data 141 and flow data 144, respectively. The oil flow controller 134 is also shown as receiving a variable consumption demand 146, which may originate from another controller, such as an engine controller. Alternatively, the oil flow controller 134 may receive operational data in place of the variable consumption demand 146 and determine the variable consumption demand 146 within the oil flow controller 134. For example, another device may send operational details related to the operation of the oil consumer 138, and the oil flow controller 134 may use the operational details to determine the variable consumption demand. The determination of the variable consumption demand 146 may be performed by any suitable algorithm, lookup table, or model, to name a few non-limiting examples. The oil flow controller 134 may use the variable consumption demand (whether provided to the oil flow controller 134 or determined within the oil flow controller 134) in conjunction with the flow rate data 141 (in some embodiments, the flow data 144) to determine the pump control command 148 and the valve command 150. As described above, the oil flow controller 134 may determine a total variable consumption demand (e.g., by summing the variable consumption demands of each oil consumer 138) to determine the pump control command 148. For example, if the oil flow controller 134 determines that the power gearbox 138a and the engine shaft bearing 138b require lubrication, but the accessories 138c and the generator 138d do not require lubrication, the oil flow controller 134 may sum the variable consumption demands from each of 138a and 138b to form the total variable consumption demand. At another point in time, if the oil flow controller 134 determines that the generator 138d requires lubricant for cooling at the same time as 138a and 138b, the oil flow controller 134 may sum the variable consumption demands from each of 138a, 138b, and 138d to form the total variable consumption demand. Thus, in some embodiments, the total variable consumption demand may be a time-varying determination that represents different demands from different numbers of consumers. The variable consumption demand for any given consumer 123a-138e can be a variable amount between minimum flow (e.g., valve closed to produce a no flow condition) and maximum flow (e.g., valve fully open to produce a maximum flow condition). In some embodiments, the variable consumption demand can be an intermediate value between the minimum flow condition and the maximum flow condition.

[0053] In addition to and / or as an alternative to the above, the oil flow controller 134 can also determine an independent valve command 150 for each individual oil flow control valve 130 to provide an appropriate oil flow to meet the lubrication and / or thermal requirements of the oil consumer 138. In some embodiments, the valve 130 associated with each of the consumers 138a-138e can be commanded to open or close, for example, in an embodiment including full lubricant flow or no lubricant flow. In further embodiments, the valve 130 associated with each consumer 138a-138e can provide an intermediate valve position between the fully open and fully closed positions. Any number of intermediate valve positions can be provided. In some forms, the valve command issued by the oil flow controller 134 can be continuously variable, while in other forms, it is a command with a quantized value (e.g., a digital command within the oil flow controller 134 that is converted into an analog output for driving the valve 130). As just one example, the oil flow controller 134 may issue a valve command to the valve 130 associated with the power gearbox 138a to provide a partial lubricant flow to the power gearbox 138a, while the oil flow controller 134 provides a discrete valve opening command to the valve 130 associated with the accessory 138c to provide a fully open or fully closed position. In some forms, each valve 130 associated with a respective consumer 138a-138e may be different from one another, for example, the valve 130 associated with the accessory 138c provides a fully open or fully closed position, while the valve 130 associated with the power gearbox 138a provides at least one intermediate position between the fully open and fully closed positions.

[0054] In one mode of operation, the oil flow controller 134 may provide a minimum pressure to each oil consumer 138, and if sufficient capacity remains in the variable flow oil pump, additional oil flow may be commanded via the pump control commands 148 to produce additional flow for thermal cooling purposes. For example, if the variable flow oil pump 124 has a maximum flow at a given flow rate, and if one or more consumers 138 require a minimum pressure for lubrication purposes, while one or more other consumers 138 require lubricant for cooling purposes, the oil flow controller 134 may, via commands, preferentially allocate lubricant to the valve 130 associated with each consumer 138 for lubrication purposes, and thereafter allocate the remaining flow capacity for cooling purposes (e.g., the capacity associated with the consumer 138 requested for lubrication purposes minus the maximum flow capacity) to the other consumers 138 requesting for cooling purposes. If the remaining capacity is insufficient to provide thermal cooling purposes, the oil flow controller 134 may deny the request for thermal cooling purposes, or, if in the example of a variable flow valve 130, issue a partial valve command to partially provide lubricant flow for thermal cooling purposes.

[0055] In addition to and / or as an alternative to the above, the oil flow controller 134 can provide open loop commands (e.g., no feedback or other estimation to provide dynamic adjustment of lubricant flow rate) to one or both of the variable flow oil pump 124 and the oil flow control valve 130, or can provide closed loop commands (e.g., feedback or estimation to provide dynamic adjustment of lubricant flow rate). For example, the oil flow controller 134 can determine the flow rate of oil delivered from the oil flow control valve 130 and compare it to the desired flow rate of oil determined based on the variable consumption demand 146. In some embodiments, a flow rate sensor and / or a pressure sensor can be used directly to provide feedback of the amount of lubricant delivered, or can be used to calculate the flow rate of the amount of lubricant delivered. The oil flow controller 134 can use any of a number of potential variables to close the loop, including flow rate, flow pressure, or lubricant demand. For example, if the oil flow controller 134 closes the loop based on lubricant demand, the oil flow controller 134 can include control functions to convert the measured lubricant pressure into an actual flow rate and convert the variable consumption demand from any given consumer 138 into a desired flow rate. If there is an error in the flow rate from the oil flow control valve 130 (eg, a difference between a desired flow rate and an actual flow rate provided by the oil flow control valve 130 ), the oil flow controller 134 may command the oil flow control valve 130 to open or close according to the error.

[0056] Now go to Figure 6 , one or more portions of the oil flow controller 134 may be implemented using the computing device 152, Figure 5 An embodiment of the oil flow controller 134 is shown. The computing device 152 may include one or more processors 152A and one or more memory devices 152B. The one or more processors 152A may include any suitable processing device, such as a microprocessor, a microcontroller, an integrated circuit, a logic device, and / or other suitable processing device. The one or more memory devices 152B may include one or more computer-readable media, including but not limited to non-transitory computer-readable media, RAM, ROM, hard disk drives, flash drives, and / or other memory devices.

[0057] One or more memory devices 152B may store information accessible to one or more processors 152A, including computer-readable instructions 152C that may be executed by one or more processors 152A. Instructions 152C may be any set of instructions that, when executed by one or more processors 152A, will cause one or more processors 152A to perform operations. In some embodiments, instructions 152C may be executed by one or more processors 152A to cause one or more processors 152A to perform operations, such as any operations and functions that the controller and / or computing device 152 is configured for, operations of any of the above systems (e.g., valve 223, etc.) as described herein, and / or any other operations or functions of one or more computing devices 152 (e.g., as a full authority digital engine controller). Instructions 152C may be software written in any suitable programming language, or may be implemented in hardware. Additionally, and / or alternatively, instructions 152C may be executed in logically and / or virtually separate threads on one or more processors 152A. One or more memory devices 152B may also store data 152D that may be accessed by one or more processors 152A. For example, data 152D may include data indicative of outside air conditions, power flows, data indicative of engine / aircraft operating conditions, and / or any other data and / or information described herein.

[0058] The computing device 152 may also include a network interface 152E for communicating with other components of the systems described herein (e.g., via a communication network). The network interface 152E may include any suitable components for interfacing with one or more networks, including, for example, transmitters, receivers, ports, controllers, antennas, and / or other suitable components. One or more devices may be configured to receive one or more commands from the computing device 152 or to provide one or more commands to the computing device 152.

[0059] Network interface 152E may include any suitable components for interfacing with one or more networks, including, for example, transmitters, receivers, ports, controllers, antennas, and / or other suitable components.

[0060] The technology discussed herein relates to computer-based systems and actions taken by computer-based systems and information sent to and from computer-based systems. Those of ordinary skill in the art will recognize that the inherent flexibility of computer-based systems allows for multiple possible configurations, combinations, and divisions of tasks and functions between and among components. For example, the processes discussed herein can be implemented using a single computing device or multiple computing devices working in combination. Databases, memories, instructions, and applications can be implemented on a single system or distributed on multiple systems. Distributed components can operate sequentially or in parallel.

[0061] Figure 7 A method 154 for operating a gas turbine engine oil flow control system 122 is disclosed. One or more steps of the method 154 can be implemented using the oil flow controller 134 discussed elsewhere herein. Any step of the method 154 can be implemented using a variety of control feedback techniques, including classical control, modern control, and robust control. In addition, any step can be implemented using a data-driven model developed from machine learning or any other artificial intelligence technology. Data useful to the oil flow controller 134 can include sensed data as well as calculated data.

[0062] The method 154 includes, at step 158, receiving power from the operation of the gas turbine engine via a variable flow oil pump to provide a pump variable oil flow 126. The variable flow oil pump 124 may receive mechanical power, for example, via a power take-off from the gas turbine engine 10, or may be electrically driven and configured to receive power from, for example, a generator 138d. At step 160, the method 154 includes delivering the pump variable oil flow 126 to oil consumers 138 associated with the operation of the gas turbine engine 10. In some embodiments, when the variable flow oil pump 124 operates, moving mechanical components within the variable flow oil pump 124 are actuated to provide pressurization and / or power to pump lubricant to one or more consumers 138. Step 162 includes controlling the oil flow control valve 130 to vary the valve variable oil flow 132 based on the variable consumption demand 146 of the oil consumer 138. As described above, the oil flow control valve 130 may be controlled to provide an open or closed position, or a variable position between the open and closed positions, in only some embodiments. The method 154 may also include comparing the expected consumption requirement of a given consumer 138 with the actual consumption of the given consumer 138. Comparing the expected consumption with the actual consumption may include converting the flow rate or flow characteristics of the lubricant to the actual consumption (e.g., by a lookup table or other conversion technique) to compare with the expected consumption requirement. Alternatively, the expected consumption requirement may be converted to a flow rate or flow characteristic (e.g., by a lookup table or other conversion technique) and then compared with the actual flow rate and / or flow characteristic. As a result of the control at step 162, step 164 changes the pump variable oil flow to the valve variable oil flow 132 by operating the oil flow control valve 130. In some embodiments, the method 154 may also include generating flow rate data 141 indicating the rate of oil to the oil consumer 138. The method 154 may additionally include controlling the variable flow oil pump 124 based on the flow rate data 141. The method 154 may additionally and / or alternatively include controlling the variable flow oil pump 124 based on the sum of the variable consumption requirements 146 of each oil consumer in the plurality of oil consumers 138.

[0063] A technical advantage of the oil flow control system 122 is that it can provide customized lubrication and / or cooling for any oil consumer 138 associated with the operation of the gas turbine engine 10. If one of the oil consumers 138 requires a greater flow rate for one or both of lubrication and cooling purposes, (e.g., in some embodiments, the generator 138d may only require cooling, which may vary with the operation of the gas turbine engine 10, while the power gearbox 138a may require both lubrication and cooling at different times during the operation of the gas turbine engine 10), the oil flow controller 134 may command the variable flow oil pump 124 to change its pump variable oil flow 126, and the oil flow control valve 130 may then adjust the valve variable oil flow 132 for any oil consumer 138 that requires a change, and / or adjust the valve variable oil flow 132 for any other oil consumer 138 that may be affected by a change in the pump variable oil flow 126 generated by the variable flow oil pump 124. For example, an oil consumer 138 whose flow rate varies with changes in the pump variable oil flow 126 may have its valve position changed by the oil flow controller 134 to mitigate any changes in its valve variable oil flow 132 without requiring a change in flow rate, but without a change in the valve setting of its associated oil flow control valve 130 .

[0064] Further aspects are provided by the subject matter of the following clauses:

[0065] 1. A gas turbine engine oil flow control system, comprising: a gas turbine engine, the gas turbine engine being configured to provide power during operation of the gas turbine engine; a variable flow oil pump, the variable flow oil pump being configured to generate a pump variable oil flow; an oil flow control valve, the oil flow control valve being fluidically connected to the variable flow oil pump, the oil flow control valve being configured to change a valve variable oil flow through the oil flow control valve; an oil consumer, the oil consumer being associated with operation of the gas turbine engine and being configured to receive the valve variable oil flow changed by the oil flow control valve, the oil consumer having a variable consumption demand for oil delivery; and an oil flow controller, the oil flow controller being configured to generate a valve command for the oil flow control valve based on the variable consumption demand of the oil consumer.

[0066] 1. A gas turbine engine oil flow control system, comprising: a variable flow oil pump, the variable flow oil pump being configured to generate a pump variable oil flow during operation of the gas turbine engine; an oil flow control valve, the oil flow control valve being fluidly connected to the variable flow oil pump, the oil flow control valve being configured to change the pump variable oil flow to a valve variable oil flow through operation of the oil flow control valve; an oil consumer, the oil consumer being associated with the operation of the gas turbine engine and being configured to receive the valve variable oil flow changed by the oil flow control valve, the oil consumer having a variable consumption demand for oil delivery; and an oil flow controller, the oil flow controller being configured to generate a valve command for the oil flow control valve based on the variable consumption demand of the oil consumer.

[0067] A gas turbine engine oil flow control system according to the preceding clause, wherein the valve variable oil flow is used as a lubricant in the oil consumer, and wherein the valve variable oil flow is used as a heat transfer fluid in the oil consumer.

[0068] A gas turbine engine oil flow control system according to any preceding clause, further comprising a flow rate sensor in fluid communication with the oil consumer, the flow rate sensor configured to generate flow rate data indicative of the valve variable oil flow to the oil consumer.

[0069] A gas turbine engine oil flow control system according to any preceding clause, wherein said oil flow controller is configured to generate a pump control command for said variable flow oil pump based on said flow rate data from said flow rate sensor to produce a variable oil flow to said pump.

[0070] A gas turbine engine oil flow control system as described in any preceding clause, wherein the oil consumer comprises a plurality of oil consumers.

[0071] A gas turbine engine oil flow control system as described in any preceding clause, wherein the plurality of oil consumers are configured in an oil flow arrangement parallel to one another.

[0072] A gas turbine engine oil flow control system according to any preceding clause, wherein each of the plurality of oil consumers has a variable consumption demand for oil delivery, and wherein the total demand is the sum of the variable consumption demands associated with each of the plurality of oil consumers.

[0073] A gas turbine engine oil flow control system as described in any preceding clause, wherein the plurality of oil consumers includes at least two of: a power gearbox; an engine shaft bearing; accessories; and a generator.

[0074] 14. The oil flow control system of a gas turbine engine, comprising: a gas turbine engine configured to provide power during operation of the gas turbine engine; a variable flow oil pump configured to receive power from the gas turbine engine and generate a pump variable oil flow; an oil consumer associated with the operation of the gas turbine engine and in fluid communication with the variable flow oil pump, the oil consumer having a variable consumption demand for oil delivery; a first flow rate sensor configured to generate first flow rate data indicating a rate of oil to the oil consumer; and an oil flow controller configured to generate a pump control command based on the first flow rate data to control the variable flow oil pump to change the pump variable oil flow.

[0075] 1. A gas turbine engine oil flow control system, comprising: a variable flow oil pump, the variable flow oil pump being configured to receive power from the gas turbine engine and generate a pump variable oil flow during operation of the gas turbine engine; an oil consumer, the oil consumer being associated with the operation of the gas turbine engine and being fluidically connected to the variable flow oil pump, the oil consumer having a variable consumption demand for oil delivery; a first flow rate sensor, the first flow rate sensor being configured to generate first flow rate data indicating a rate of oil to the oil consumer; and an oil flow controller, the oil flow controller being configured to generate a pump control command based on the first flow rate data to control the variable flow oil pump to change the pump variable oil flow.

[0076] The gas turbine engine oil flow control system according to the preceding clause further comprises an oil flow control valve connected to the variable flow oil pump fluid, the oil flow control valve being configured to change the pump variable oil flow to a valve variable oil flow through operation of the oil flow control valve, and wherein the rate of the oil to the oil consumer is the valve variable oil flow.

[0077] A gas turbine engine oil flow control system as described in any preceding clause, wherein the oil flow controller is further configured to generate a valve command for the oil flow control valve based on the variable consumption demand of the oil consumer.

[0078] A gas turbine engine oil flow control system according to any preceding clause, further comprising a second flow rate sensor positioned downstream of the oil consumer, the second flow rate sensor configured to generate second flow rate data indicative of a rate of oil to the oil consumer.

[0079] A gas turbine engine oil flow control system according to any preceding clause, further comprising an oil tank in fluid communication with the variable flow oil pump and a heat exchanger in fluid communication with the variable flow oil pump.

[0080] A gas turbine engine oil flow control system as described in any preceding clause, wherein the heat exchanger is in downstream fluid communication with the variable flow oil pump and in upstream fluid communication with the oil consumer.

[0081] A gas turbine engine oil flow control system according to any preceding clause, wherein an oil flow control valve is in downstream fluid communication with the heat exchanger, and wherein the oil consumer is in downstream communication with the oil flow control valve.

[0082] A gas turbine engine oil flow control system according to any preceding clause, wherein the oil consumer comprises a plurality of oil consumers, wherein each of the plurality of oil consumers comprises a variable consumption demand, wherein during operation of the plurality of oil consumers, the oil flow controller determines the pump control command based on a sum of the variable consumption demands of the plurality of oil consumers.

[0083] A gas turbine engine oil flow control system as described in any preceding clause, wherein the oil flow controller is configured to generate the pump control command based on the oil demand of the oil consumer.

[0084] A gas turbine engine oil flow control system according to any preceding clause, further comprising an oil flow passage in fluid communication with said oil consumer, said variable flow oil pump and said oil flow control valve;

[0085] A method for operating a gas turbine engine oil flow control system, comprising: generating power during operation of the gas turbine engine; receiving power to provide a pump variable oil flow; delivering oil from the pump variable oil flow to an oil consumer associated with operation of the gas turbine engine; controlling an oil flow control valve to vary the valve variable oil flow based on a variable consumption demand of the oil consumer; and varying the valve variable oil flow through the oil flow control valve as a result of the control.

[0086] A method for operating an oil flow control system for a gas turbine engine, comprising: receiving power from the operation of a gas turbine engine through a variable flow oil pump to provide a pump variable oil flow; delivering oil from the pump variable oil flow to an oil consumer associated with the operation of the gas turbine engine; controlling an oil flow control valve to change the valve variable oil flow based on a variable consumption demand of the oil consumer; and as a result of the control, changing the pump variable oil flow to the valve variable oil flow through the operation of the oil flow control valve.

[0087] A method as described in the preceding clause, further comprising generating flow rate data indicative of a rate of oil to the oil consumer.

[0088] A method as in any preceding clause, further comprising controlling the variable flow oil pump based on the flow rate data.

[0089] A method according to any preceding clause, wherein the oil consumer comprises a plurality of oil consumers each having a variable consumption demand, and the method further comprises controlling the variable flow oil pump based on a sum of the variable consumption demands of each of the plurality of oil consumers.

[0090] 14. The control device of claim 13, wherein the at least one oil flow control circuit is configured to control the flow of oil from the oil flow control circuit to a level that is proportional to the speed of the oil flow. The at least one oil flow control circuit is configured to control the flow of oil from the oil flow control circuit to a level that is proportional to the speed of the oil flow.

[0091] The gas turbine engine control arrangement according to the preceding clause, further comprising an oil flow controller, wherein the oil flow controller is configured to generate a pump control command based on the first flow rate data to change a pumping rate of the oil flow control circuit.

[0092] A gas turbine engine oil flow control system according to the preceding clause, wherein the variable oil flow is used as a lubricant in the oil consumer, and wherein the variable oil flow is used as a heat transfer fluid in the oil consumer.

[0093] A gas turbine engine oil flow control system according to any preceding clause, further comprising a flow rate sensor in fluid communication with the oil consumer, the flow rate sensor configured to generate flow rate data indicative of the variable oil flow to the oil consumer.

[0094] A gas turbine engine oil flow control system as described in any preceding clause, wherein the oil flow controller compares the variable consumption requirement of the oil consumer to actual consumption based on at least one of flow rate and flow characteristics.

[0095] A gas turbine engine oil flow control system as described in any preceding clause wherein the oil flow controller compares at least one of a flow rate and a flow characteristic to a desired flow rate and a desired flow characteristic, respectively, based on a variable consumption demand of the oil consumer.

[0096] A gas turbine engine oil flow control system as described in any preceding clause, wherein the oil flow controller is configured to generate a pump control command for the variable flow oil pump based on the flow rate data from the flow rate sensor.

[0097] A gas turbine engine oil flow control system as described in any preceding clause, wherein the oil consumer comprises a plurality of oil consumers.

[0098] A gas turbine engine oil flow control system as described in any preceding clause, wherein the plurality of oil consumers are configured in an oil flow arrangement parallel to one another.

[0099] A gas turbine engine oil flow control system according to any preceding clause, wherein each of the plurality of oil consumers has a variable consumption demand for oil delivery, and wherein the total demand is the sum of the variable consumption demands associated with each of the plurality of oil consumers.

[0100] A gas turbine engine oil flow control system as described in any preceding clause, wherein the plurality of oil consumers includes at least two of: a power gearbox; an engine shaft bearing; accessories; and a generator.

[0101] This written description uses examples to disclose the present disclosure, including the best mode, and also to enable any person skilled in the art to practice the present disclosure, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the present disclosure is defined by the claims, and may include other examples that occur to one skilled in the art. Such other examples are intended to fall within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements that do not differ substantially from the literal language of the claims.

Claims

1. A gas turbine engine oil flow control system, characterized in that: include: a variable flow oil pump configured to produce a pump variable oil flow during operation of the gas turbine engine; an oil flow control valve in fluid communication with the variable flow oil pump, the oil flow control valve being configured to change the pump variable oil flow to a valve variable oil flow through operation of the oil flow control valve; an oil consumer associated with operation of the gas turbine engine and configured to receive the valve variable oil flow varied by the oil flow control valve, the oil consumer having a variable consumption demand for oil delivery; and An oil flow controller is configured to generate a valve command for the oil flow control valve based on the variable consumption demand of the oil consumer.

2. The gas turbine engine oil flow control system according to claim 1, characterized in that: in, The valve-variable oil flow is used as a lubricant in the oil consumer, and wherein the valve-variable oil flow is used as a heat transfer fluid in the oil consumer.

3. The gas turbine engine oil flow control system according to claim 1, characterized in that: Further included is a flow rate sensor in fluid communication with the oil consumer, the flow rate sensor configured to generate flow rate data indicative of the valved variable oil flow to the oil consumer.

4. The gas turbine engine oil flow control system according to claim 3, characterized in that: in, The oil flow controller is configured to generate a pump control command for the variable flow oil pump based on the flow rate data from the flow rate sensor to produce a variable oil flow to the pump.

5. The gas turbine engine oil flow control system according to claim 1, characterized in that: in, The oil consumer includes a plurality of oil consumers.

6. The gas turbine engine oil flow control system according to claim 5, characterized in that: in, The plurality of oil consumers are configured in an oil flow arrangement parallel to one another.

7. The gas turbine engine oil flow control system according to claim 6, characterized in that: in, Each of the plurality of oil consumers has a variable consumption demand for oil delivery, and wherein the total demand is a sum of the variable consumption demands associated with each of the plurality of oil consumers.

8. The gas turbine engine oil flow control system according to claim 5, characterized in that: in, The plurality of oil consumers include at least two of: a power gearbox; an engine shaft bearing; accessories; and a generator.

9. A gas turbine engine oil flow control system, characterized in that: include: a variable flow oil pump configured to receive power from the gas turbine engine and produce a pump variable oil flow during operation of the gas turbine engine; an oil consumer associated with operation of the gas turbine engine and in fluid communication with the variable flow oil pump, the oil consumer having a variable consumption demand for oil delivery; a first flow rate sensor configured to generate first flow rate data indicative of a rate of oil to the oil consumer; as well as An oil flow controller is configured to generate a pump control command based on the first flow rate data to control the variable flow oil pump to change the variable oil flow of the pump.

10. The gas turbine engine oil flow control system according to claim 9, characterized in that: Further comprising an oil flow control valve in fluid communication with the variable flow oil pump, the oil flow control valve being configured to change the pump variable oil flow to a valve variable oil flow through operation of the oil flow control valve, and wherein the rate of the oil to the oil consumer is the valve variable oil flow.

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