Patent Description:
In fuel delivery systems within gas turbine engines, a boost pump may be required to deliver fuel to a component such as a combustor. Due to different flow requirements at different phases of flight and engine operation, the boost pump is typically oversized and not optimized for most of its standard operating range, which may result in wasted power, excess heat and operation inefficiencies at normal cruise/low power conditions.

Disclosed is a fuel system of an aircraft engine, including: a boost pump having an input and an output; one or more selector valves; a first component pump having an input fluidly coupled to the output of the boost pump and an output of the first component pump is configured to direct fuel to a first component via the one or more selector valves; and a second component pump having an input that is selectively coupled to either the input or the output of the boost pump by the one or more selector valves, and an output of the second component pump is fluidly coupled to a second component and selectively coupled to the first component by the one or more selector valves.

In addition to one or more aspects of the system disclosed herein or as an alternate, the system further includes a fuel filter fluidly coupled to the output of the boost pump.

In addition to one or more aspects of the system disclosed herein or as an alternate, the system further includes a plurality of flowpaths, including: a first flowpath extending between the output of the boost pump and the input of the first component pump, wherein the fuel filter is disposed along the first flowpath; a second flowpath extending between the output of the first component pump and the first component via the one or more selector valves; a third flowpath extending between the input of the boost pump and the input of the second component pump via the one or more selector valves; a fourth flowpath extending between the output of the second component pump and the second component; a fifth flowpath extending between the fourth flowpath and the first component via the one or more selector valves; and a sixth flowpath extending from the first flowpath, between the fuel filter and the first component pump, to the third flowpath via the one or more selector valves.

In addition to one or more aspects of the system disclosed herein or as an alternate, the system further includes an engine controller configured to: determine when the first component pump is offline and the first component requires fuel; and control the one or more selector valves to: direct fuel from the output of the boost pump to the second component pump via the one or more selector valves; and direct fuel from the second component pump to the first component via the one or more selector valves.

In addition to one or more aspects of the system disclosed herein or as an alternate, the one or more selector valves includes a first selector valve having: a first port that is fluidly coupled to the output of the first component pump; a second port that is fluidly coupled to the first component; and a third port that is fluidly coupled to the output of the second component pump.

In addition to one or more aspects of the system disclosed herein or as an alternate, the first selector valve further includes: a fourth port that is fluidly coupled to the output of the boost pump; a fifth port that is fluidly coupled to the input of the boost pump; and a sixth port that is fluidly coupled to the input of the second component pump.

In addition to one or more aspects of the system disclosed herein or as an alternate, the system further includes a solenoid operationally coupled to the first selector valve.

In addition to one or more aspects of the system disclosed herein or as an alternate, the one or more selector valves includes a second selector valve, the second selector valve including: a fourth port that is fluidly coupled to the output of the boost pump; a fifth port that is fluidly coupled to the input of the boost pump; and a sixth port that is fluidly coupled to the input of the second component pump.

In addition to one or more aspects of the system disclosed herein or as an alternate, the system further includes a solenoid operationally coupled to the first selector valve and the second selector valve.

In addition to one or more aspects of the system disclosed herein or as an alternate, the system further includes a first solenoid operationally coupled to the first selector valve; and a second solenoid operationally coupled to the second selector valve.

Further disclosed is an aircraft including: a gas turbine engine that includes a fuel system having one or more of the aspect disclosed herein and first and second components; and a fuel source fluidly coupled to the fuel system, wherein the fuel system is configured to direct fuel from the fuel source to the first and second components.

In addition to one or more aspects of the aircraft disclosed herein or as an alternate, the aircraft further includes a filter fluidly coupled to the output of the boost pump.

In addition to one or more aspects of the aircraft disclosed herein or as an alternate, the aircraft further includes a plurality of flowpaths, including: a first flowpath extending between the output of the boost pump and the input of the first component pump, wherein a fuel filter is disposed along the first flowpath; a second flowpath extending between the output of the first component pump and the first component via the one or more selector valves; a third flowpath extending between the input of the boost pump and the input of the second component pump via the one or more selector valves; a fourth flowpath extending between the output of the second component pump and the second component; a fifth flowpath extending between the fourth flowpath and the first component via the one or more selector valves; and a sixth flowpath extending from the first flowpath, between the fuel filter and the first component pump, to the third flowpath via the one or more selector valves.

In addition to one or more aspects of the aircraft disclosed herein or as an alternate, the first component is a combustor and the second component is an afterburner.

In addition to one or more aspects of the aircraft disclosed herein or as an alternate, the aircraft further includes an engine controller configured to: determine when the first component pump is offline and the combustor requires fuel; and control the one or more selector valves to: direct fuel from the output of the boost pump to the second component pump via the one or more selector valves; and direct fuel from the second component pump to the first component via the one or more selector valves.

In addition to one or more aspects of the aircraft disclosed herein or as an alternate, the engine controller is a full authority digital engine controller.

<FIG> and <FIG> show a fuel system <NUM> of an engine <NUM>, which may be a gas turbine engine. The engine <NUM> is controlled by an engine controller <NUM> which may be full authority digital engine controller (FADEC), in an aircraft <NUM> having a fuel source <NUM>. The fuel system <NUM> may include a boost pump <NUM>, having an input <NUM> and an output <NUM>, for transferring fuel generally in a downstream flow direction <NUM>. The fuel system <NUM> includes multiple dedicated component pumps, including first and second component pumps <NUM>, <NUM>, to feed fuel to respective components, such as first and second components <NUM>, <NUM>. The first component <NUM> may be a combustor that requires operating on filtered fuel, e.g., utilizing fuel filter <NUM>. The second component <NUM> may be an afterburner that may not require filtered fuel. The filter <NUM>, between the boost pump <NUM> and the first pump <NUM>, may be housed within a fuel system interstage <NUM> (only shown in <FIG> for brevity but is generally applicable to each embodiment disclosed herein). The fuel system interstage <NUM> may house a number of components besides the filter <NUM>, including a fuel filter bypass valve, fuel oil coolers, fuel air heat exchangers, generator heat exchangers, etc..

Due to its limited operational parameters, the second component pump <NUM> may be configured handle the second component <NUM> throughout its operational range without a boost from the boost pump <NUM>. The first component pump <NUM> maybe sized to efficiently handle operation of the first component <NUM> during its normal engine operation phases. However, during high power conditions such as takeoff, the first component pump <NUM> may require a boost assist from the boost pump <NUM> in order for the first component pump <NUM> to operate sufficiently. By only requiring a boost to the first component pump <NUM> during limited operational parameters of the first component <NUM>, the boost pump <NUM> may be smaller and more efficient than if it was required to normally boost both first and second component pumps <NUM>, <NUM>.

There may be a situation in which the first component pump <NUM> enters a failure mode and must be bypassed. The disclosed embodiments, as indicated below, also provide for a backup configuration in which filtered and boosted flow is provided to the first component <NUM> via the second component pump <NUM>. As shown in the figures, one or more selector valves <NUM> is provided in the fuel system <NUM>, which enables bypassing the first component pump <NUM> and directing filtered and boosted flow to the first component <NUM> via the second component pump <NUM>.

As shown in <FIG> and <FIG>, the one or more selector vales includes a first valve <NUM>. The first component pump <NUM> has an input <NUM> fluidly coupled to the output <NUM> of the boost pump <NUM>. An output <NUM> of the first component pump <NUM> is configured to direct fuel to the first component <NUM> via the first valve <NUM>. That is, the output <NUM> of the first component pump <NUM> and the first component <NUM> are both connected to the first valve <NUM>. The second component pump <NUM> has an input <NUM> that is selectively coupled to either the input <NUM> (<FIG>), which is not boosted, or output <NUM> (<FIG>) of the boost pump <NUM> by the first valve <NUM>. That is, the input <NUM> and output <NUM> of the boost pump <NUM> are both connected to the first valve <NUM>. An output <NUM> of the second component pump <NUM> is fluidly coupled to the second component <NUM>. The output <NUM> of the second component pump <NUM> is also selectively coupled to the first component <NUM> by the first valve <NUM>. That is, the output <NUM> of the second component pump <NUM> is also connected to the first valve <NUM>. The fuel filter <NUM> is fluidly coupled to the output <NUM> of the boost pump <NUM>, between the boost pump <NUM> and the first component pump <NUM>. As indicated, the first component <NUM> may require boosted and filtered fuel but the second component <NUM> may not require boosted and filtered fuel.

A plurality of flowpaths extend through the system <NUM> and fluidly couple the components of it. A first flowpath <NUM> extends between the output <NUM> of the boost pump <NUM> and the input <NUM> of the first component pump <NUM>. A second flowpath <NUM> extends between the output <NUM> of the first component pump <NUM> and the first component <NUM> via the first valve <NUM>. Thus a first portion <NUM> of the second flowpath <NUM> extends between the output <NUM> of the first component pump <NUM> and the first valve <NUM> and a second portion of the second flowpath <NUM> extends from the first valve <NUM> toward the first component <NUM>. A third flowpath <NUM> extends between the input <NUM> of the boost pump <NUM> and the input <NUM> of the second component pump <NUM> via the first valve <NUM>. Thus, a first portion <NUM> of the third flowpath <NUM> is between the input <NUM> of the boost pump <NUM> and the first valve <NUM> and a second portion <NUM> of the third flowpath <NUM> is between the first valve <NUM> and the second component pump <NUM>. The fuel filter <NUM> is disposed along the third flowpath <NUM>. A fourth flowpath <NUM> extends between the output <NUM> of the second component pump <NUM> and the second component <NUM>. A fifth flowpath <NUM> extends between the fourth flowpath <NUM> and the first component <NUM> via the first valve <NUM>. That is, a branch off the fourth flowpath <NUM> is connected to the first valve <NUM> to define the fifth flowpath <NUM>. A sixth flowpath <NUM> extends from the first flowpath <NUM>, at a location between the fuel filter <NUM> and the first component pump <NUM>, to the third flowpath <NUM> via the first valve <NUM>. That is, the sixth flowpath <NUM> is a branch off the first flowpath <NUM>, downstream of the fuel filter <NUM>, that extends to the first valve.

A plurality of ports are defined by the first valve <NUM> for fluidly coupling the components of the fuel system <NUM> via the flowpaths of the fuel system <NUM>. A first port <NUM> of the first valve <NUM> is fluidly coupled to the output <NUM> of the first component pump <NUM> via the first portion <NUM> of the second flowpath <NUM>. A second port <NUM> of the first valve <NUM> is fluidly coupled to the first component <NUM> via the second portion <NUM> of the second flowpath <NUM>. A third port <NUM> of the first valve <NUM> is fluidly coupled to the output <NUM> of the second component pump <NUM> via the fifth flowpath <NUM> branch of the fourth flowpath <NUM>.

The first valve <NUM> has a first internal passage <NUM> that can selectively be in a first configuration (<FIG>) that connects the first port <NUM> with the second port <NUM> to fluidly connect the first and second portions <NUM>, <NUM> of the second flowpath <NUM>. Otherwise, in a second configuration (<FIG>), the first internal passage <NUM> may connect the third port <NUM> with the second port <NUM>, to fluidly connect the fifth flowpath <NUM> branch of the fourth flowpath <NUM> with the second portion <NUM> of the second flowpath <NUM>. The first configuration feeds the first component <NUM> from the first component pump <NUM> and the second configuration fees the first component <NUM> from the second component pump <NUM>.

A fourth port <NUM> of the first valve <NUM> is fluidly coupled to the output <NUM> of the boost pump <NUM> via the sixth flowpath <NUM> branch of the third flowpath <NUM>. A fifth port <NUM> of the first valve <NUM> is fluidly coupled to the input <NUM> of the boost pump <NUM> via the first portion <NUM> of the third flowpath <NUM>. A sixth port <NUM> of the first valve <NUM> is fluidly coupled to the input <NUM> of the second component pump <NUM> via the second portion <NUM> of the third flowpath <NUM>.

The first valve <NUM> has a second internal passage <NUM> that is fluidly isolated from the first internal passage <NUM>. The second internal passage <NUM> can selectively be in a first configuration (<FIG>) that connects the fifth port <NUM> with the sixth port <NUM> to direct fuel that is not boosted or filtered to the second component pump <NUM>. The second internal passage <NUM> can selectively be in a second configuration (<FIG>) that connects the fourth port <NUM> with the sixth port <NUM> to direct fuel that is boosted and filtered to the second component pump <NUM>. That is, the second configuration of the second internal passage <NUM> bypasses the first component pump <NUM>.

As shown in <FIG> and <FIG>, a solenoid <NUM> is operationally coupled to the first valve <NUM>. The solenoid <NUM> is configured to simultaneously position the first internal passage <NUM> and second internal passage <NUM> in their first configuration (<FIG>). In this configuration, defining a first configuration of the first valve <NUM>, the first component <NUM> receives fuel from the first component pump <NUM> and the second component <NUM> receives fuel from the second component pump <NUM>. The solenoid <NUM> is configured to simultaneously position the first internal passage <NUM> and second internal passage <NUM> in their second configuration (<FIG>). In this configuration, defining a second configuration of the first valve <NUM>, the first component <NUM> receives fuel from the second component pump <NUM>.

While the first valve <NUM> is in its first configuration (<FIG>), the engine controller <NUM> is configured to determine when the first component pump <NUM> is offline, e.g., due to failure, and the first component <NUM> requires fuel. In response to this condition, the engine controller <NUM> is configured to control the solenoid <NUM> to put the first valve <NUM> in its second configuration (<FIG>), to direct fuel to the first component <NUM> via the boost pump <NUM> and the second component pump <NUM>. In the second configuration, the second component <NUM> is deactivated.

In another embodiment, <FIG> and <FIG> show a fuel system 100A of an engine 110A, which may be a gas turbine engine. The engine 110A is controlled by an engine controller 115A which may be full authority digital engine controller (FADEC), in an aircraft 120A having a fuel source 125A. The fuel system 100A may include a boost pump 130A, having an input 1301A and an output 1302A, for transferring fuel generally in a downstream flow direction 135A. The fuel system 100A includes multiple dedicated component pumps, including first and second component pumps 141A, 142A, to feed fuel to respective components, such as first and second components 151A, 152A. The first component 151A may be a combustor that requires operating on filtered fuel, e.g., utilizing fuel filter 160A. The second component 152A may be an afterburner that may not require filtered fuel.

Due to its limited operational parameters, the second component pump 142A may be configured handle the second component 152A throughout its operational range without a boost from the boost pump 130A. The first component pump 141A maybe sized to efficiently handle operation of the first component 151A during its normal engine operation phases. However, during high power conditions such as takeoff, the first component pump 141A may require a boost assist from the boost pump 130A in order for the first component pump 141A to operate sufficiently. By only requiring a boost to the first component pump 141A during limited operational parameters of the first component 151A, the boost pump 130A may be smaller and more efficient than if it was required to normally boost both first and second component pumps 141A, 142A.

There may be a situation in which the first component pump 141A enters a failure mode and must be bypassed. The disclosed embodiments, as indicated below, also provide for a backup configuration in which filtered and boosted flow is provided to the first component 151A via the second component pump 142A. As shown in the figures, one or more selector valves 170A is provided in the fuel system 100A, which enables bypassing the first component pump 141A and directing filtered and boosted flow to the first component 151A via the second component pump 142A.

As shown in <FIG> and <FIG>, the one or more selector vales includes a first valve 171A and a second valve 172A. The first component pump 141A has an input 1411A fluidly coupled to the output 1302A of the boost pump 130A. An output 1412A of the first component pump 141A is configured to direct fuel to the first component 151A via the first valve 171A. That is, the output 1412A of the first component pump 141A and the first component 151A are both connected to the first valve 171A. The second component pump 142A has an input 1421A that is selectively coupled to either the input 1301A (<FIG>), which is not boosted, or the output 1302A (<FIG>) of the boost pump 130A by the second valve 172A. That is, the input 1421A and output 1422A of the boost pump 130A are both connected to the second valve 172A. An output 1422A of the second component pump 142A is fluidly coupled to the second component 152A. The output 1422A of the second component pump 142A is also selectively coupled to the first component 151A by the first valve 171A. That is, the output 1422A of the second component pump 142A is also connected to the first valve 171A. The fuel filter 160A is fluidly coupled to the output 1302A of the boost pump 130A, between the boost pump 130A and the first component pump 141A. As indicated, the first component 151A may require boosted and filtered fuel but the second component 152A may not require boosted and filtered fuel.

A plurality of flowpaths extend through the fuel system 100A and fluidly couple the components of it. A first flowpath 201A extends between the output 1302A of the boost pump 130A and the input 1411A of the first component pump 141A. A second flowpath 202A extends between the output 1412A of the first component pump 141A and the first component 151A via the first valve 171A. Thus a first portion 2021A of the second flowpath 202A extends between the output 1412A of the first component pump 141A and the first valve 171A and a second portion of the second flowpath 2022A extends from the first valve 171A toward the first component 151A. A third flowpath 203A extends between the input 1301A of the boost pump 130A and the input 1421A of the second component pump 142A via the second valve 172A. Thus, a first portion 2031A of the third flowpath 203A is between the input 1301A of the boost pump 130A and the first valve 171A and a second portion 2032A of the third flowpath 203A is between the second valve 172A and the second component pump 142A. The fuel filter 160A is disposed along the third flowpath 203A. A fourth flowpath 204A extends between the output 1422A of the second component pump 142A and the second component 152A. A fifth flowpath 205A extends between the fourth flowpath 204A and the first component 151A via the first valve 171A. That is, a branch off the fourth flowpath 204A is connected to the first valve 171A to define the fifth flowpath 205A. A sixth flowpath 206A extends from the first flowpath 201A, at a location between the fuel filter 160A and the first component pump 141A, to the third flowpath 203A via the second valve 172A. That is, the sixth flowpath 206A is a branch off the first flowpath 201A, downstream of the fuel filter 160A, that extends to the second valve 172A.

A plurality of ports are defined by the first valve 171A and second valve 172A for fluidly coupling the components of the fuel system 100A via the flowpaths of the fuel system <NUM>. A first port 211A of the first valve 171A is fluidly coupled to the output 1412A of the first component pump 141A via the first portion 2021A of the second flowpath 202A. A second port 212A of the first valve 171A is fluidly coupled to the first component 151A via the second portion 2022A of the second flowpath 202A. A third port 213A of the first valve 171A is fluidly coupled to the output 1422A of the second component pump 142A via the fifth flowpath 205A branch of the fourth flowpath 204A.

The first valve 171A has a first internal passage 1711A that can selectively be in a first configuration (<FIG>) that connects the first port 211A with the second port 212A to fluidly connect the first and second portions 2021A, 2022A of the second flowpath 202A. Otherwise, in a second configuration (<FIG>), the first internal passage 1711A may connect the third port 213A with the second port 212A, to fluidly connect the fifth flowpath 205A branch of the fourth flowpath 204A with the second portion 2022A of the second flowpath 202A. The first configuration feeds the first component 151A from the first component pump 141A and the second configuration fees the first component 151A from the second component pump 142A.

A fourth port 214A of the second valve 172A is fluidly coupled to the output 1302A of the boost pump 130A via the sixth flowpath 206A branch of the third flowpath 203A. A fifth port 215A of the second valve 172A is fluidly coupled to the input 1301A of the boost pump 130A via the first portion 2031A of the third flowpath 203A. A sixth port 216A of the second valve 172A is fluidly coupled to the input 1421A of the second component pump 142A via the second portion 2032A of the third flowpath 203A.

The second valve 172A has a second internal passage 1721A that is fluidly isolated from the first internal passage 1711A. The second internal passage 1721A can selectively be in a first configuration (<FIG>) that connects the fifth port 215A with the sixth port 216A to direct fuel that is not boosted or filtered to the second component pump 142A. The second internal passage 1721A can selectively be in a second configuration (<FIG>) that connects the fourth port 214A with the sixth port 216A to direct fuel that is boosted and filtered to the second component pump 142A. That is, the second configuration of the second internal passage 1721A bypasses the first component pump 141A.

As shown in <FIG> and <FIG>, a solenoid 230A is operationally coupled to the first valve 171A and the second valve 172A. The solenoid 230A is configured to simultaneously position the first internal passage 1711A and second internal passage 1721A in their first configuration (<FIG>). In this configuration, defining a first configuration of the first and second valves 171A, 172A the first component 151A receives fuel from the first component pump 141A and the second component 152A receives fuel from the second component pump 142A. The solenoid 230A is configured to simultaneously position the first internal passage 1711A and second internal passage 1721A in their second configuration (<FIG>). In this configuration, defining a second configuration of the first and second valves 171A, 172A the first component 151A receives fuel from the second component pump 141A.

While the first and second valves 171A, 172A are in their first configuration (<FIG>), the engine controller <NUM> is configured to determine when the first component pump 141A is offline, e.g., due to failure, and the first component 151A requires fuel. In response to this condition, the engine controller 115A is configured to control the solenoid 230A to put the first and second valves 171A, 172A in their second configuration (<FIG>), to direct fuel to the first component 151A via the boost pump 130A and the second component pump 142A. In the second configuration, the second component 152A is deactivated.

In a further embodiment, <FIG> and <FIG> show a fuel system 100B of an engine 110B, which may be a gas turbine engine. The engine 110B is controlled by an engine controller 115B which may be full authority digital engine controller (FADEC), in an aircraft 120B having a fuel source 125B. The fuel system 100B may include a boost pump 130B, having an input 1301B and an output 1302B, for transferring fuel generally in a downstream flow direction 135B. The fuel system 100B includes multiple dedicated component pumps, including first and second component pumps 141B, 142B, to feed fuel to respective components, such as first and second components 151B, 152B. The first component 151B may be a combustor that requires operating on filtered fuel, e.g., utilizing fuel filter 160B. The second component 152B may be an afterburner that may not require filtered fuel.

Due to its limited operational parameters, the second component pump 142B may be configured handle the second component 152B throughout its operational range without a boost from the boost pump 130B. The first component pump 141B maybe sized to efficiently handle operation of the first component 151B during its normal engine operation phases. However, during high power conditions such as takeoff, the first component pump 141B may require a boost assist from the boost pump 130B in order for the first component pump 141B to operate sufficiently. By only requiring a boost to the first component pump 141B during limited operational parameters of the first component 151B, the boost pump 130B may be smaller and more efficient than if it was required to normally boost both first and second component pumps 141B, 142B.

There may be a situation in which the first component pump 141B enters a failure mode and must be bypassed. The disclosed embodiments, as indicated below, also provide for a backup configuration in which filtered and boosted flow is provided to the first component 151B via the second component pump 142B. As shown in the figures, one or more selector valves 170B is provided in the fuel system 100B, which enables bypassing the first component pump 141B and directing filtered and boosted flow to the first component 151B via the second component pump 142B.

As shown in <FIG> and <FIG>, the one or more selector vales includes a first valve 171B and a second valve 172B. The first component pump 141B has an input 1411B fluidly coupled to the output 1302B of the boost pump 130B. An output 1412B of the first component pump 141B is configured to direct fuel to the first component 151B via the first valve 171B. That is, the output 1412B of the first component pump 141B and the first component 151B are both connected to the first valve 171B. The second component pump 142B has an input 1421B that is selectively coupled to either the input 1301B (<FIG>), which is not boosted, or the output 1302B (<FIG>) of the boost pump 130B by the second valve 172B. That is, the input 1421B and output 1422B of the boost pump 130B are both connected to the second valve 172B. An output 1422B of the second component pump 142B is fluidly coupled to the second component 152B. The output 1422B of the second component pump 142B is also selectively coupled to the first component 151B by the first valve 171B. That is, the output 1422B of the second component pump 142B is also connected to the first valve 171B. The fuel filter 160B is fluidly coupled to the output 1302B of the boost pump 130B, between the boost pump 130B and the first component pump 141B. As indicated, the first component 151B may require boosted and filtered fuel but the second component 152B may not require boosted and filtered fuel.

A plurality of flowpaths extend through the fuel system 100B and fluidly couple the components of it. A first flowpath 201B extends between the output 1302B of the boost pump 130B and the input 1411B of the first component pump 141B. A second flowpath 202B extends between the output 1412B of the first component pump 141B and the first component 151B via the first valve 171B. Thus a first portion 2021B of the second flowpath 202B extends between the output 1412B of the first component pump 141B and the first valve 171B and a second portion of the second flowpath 2022B extends from the first valve 171B toward the first component 151B. A third flowpath 203B extends between the input 1301B of the boost pump 130B and the input 1421B of the second component pump 142B via the second valve 172B. Thus, a first portion 2031B of the third flowpath 203B is between the input 1301B of the boost pump 130B and the first valve 171B and a second portion 2032B of the third flowpath 203B is between the second valve 172B and the second component pump 142B. The fuel filter 160B is disposed along the third flowpath 203B. A fourth flowpath 204B extends between the output 1422B of the second component pump 142B and the second component 152B. A fifth flowpath 205B extends between the fourth flowpath 204B and the first component 151B via the first valve 171B. That is, a branch off the fourth flowpath 204B is connected to the first valve 171B to define the fifth flowpath 205B. A sixth flowpath 206B extends from the first flowpath 201B, at a location between the fuel filter 160B and the first component pump 141B, to the third flowpath 203B via the second valve 172B. That is, the sixth flowpath 206B is a branch off the first flowpath 201B, downstream of the fuel filter 160B, that extends to the second valve 172B.

A plurality of ports are defined by the first valve 171B and second valve 172B for fluidly coupling the components of the fuel system 100B via the flowpaths of the fuel system <NUM>. A first port 211B of the first valve 171B is fluidly coupled to the output 1412B of the first component pump 141B via the first portion 2021B of the second flowpath 202B. A second port 212B of the first valve 171B is fluidly coupled to the first component 151B via the second portion 2022B of the second flowpath 202B. A third port 213B of the first valve 171B is fluidly coupled to the output 1422B of the second component pump 142B via the fifth flowpath 205B branch of the fourth flowpath 204B.

The first valve 171B has a first internal passage 1711B that can selectively be in a first configuration (<FIG>) that connects the first port 211B with the second port 212B to fluidly connect the first and second portions 2021B, 2022B of the second flowpath 202B. Otherwise, in a second configuration (<FIG>), the first internal passage 1711B may connect the third port 213B with the second port 212B, to fluidly connect the fifth flowpath 205B branch of the fourth flowpath 204B with the second portion 2022B of the second flowpath 202B. The first configuration feeds the first component 151B from the first component pump 141B and the second configuration fees the first component 151B from the second component pump 142B.

A fourth port 214B of the second valve 172B is fluidly coupled to the output 1302B of the boost pump 130B via the sixth flowpath 206B branch of the third flowpath 203B. A fifth port 215B of the second valve 172B is fluidly coupled to the input 1301B of the boost pump 130B via the first portion 2031B of the third flowpath 203B. A sixth port 216B of the second valve 172B is fluidly coupled to the input 1421B of the second component pump 142B via the second portion 2032B of the third flowpath 203B.

The second valve 172B has a second internal passage 1721B that is fluidly isolated from the first internal passage 1711B. The second internal passage 1721B can selectively be in a first configuration (<FIG>) that connects the fifth port 215B with the sixth port 216B to direct fuel that is not boosted or filtered to the second component pump 142B. The second internal passage 1721B can selectively be in a second configuration (<FIG>) that connects the fourth port 214B with the sixth port 216B to direct fuel that is boosted and filtered to the second component pump 142B. That is, the second configuration of the second internal passage 1721B bypasses the first component pump 141B.

As shown in <FIG> and <FIG>, a first solenoid 231B is operationally coupled to the first valve 171B and a second solenoid 232B is operationally coupled to the second valve 172B. The first and second solenoids 231B, 232B are configured to simultaneously position the first internal passage 1711B and second internal passage 1721B in their first configuration (<FIG>). In this configuration, defining a first configuration of the first and second valves 171B, 172B the first component 151B receives fuel from the first component pump 141B and the second component 152B receives fuel from the second component pump 142B. The first and second solenoids 231B, 232B are configured to simultaneously position the first internal passage 1711B and second internal passage 1721B in their second configuration (<FIG>). In this configuration, defining a second configuration of the first and second valves 171B, 172B the first component 151B receives fuel from the second component pump 141B.

While the first and second valves 171B, 172B are in their first configuration (<FIG>), the engine controller <NUM> is configured to determine when the first component pump 141B is offline, e.g., due to failure, and the first component 151B requires fuel. In response to this condition, the engine controller 115B is configured to control the first and second solenoids 231B, 232B to put the first and second valves 171B, 172B in their second configuration (<FIG>), to direct fuel to the first component 151B via the boost pump 130B and the second component pump 142B. In the second configuration, the second component 152B is deactivated.

The embodiment shown in <FIG> and <FIG> may be suitable for a large design envelope due to the potentially relatively large size of the selector valve. The embodiment shown in <FIG> and <FIG> may be suitable for configurations in which the two selector valves and solenoid valve are configured as a single replaceable unit. The embodiment shown in <FIG> and <FIG> may be suitable for configurations in which each selector valve and solenoid valve are configured as a replaceable unit. The pumps identified herein may be centrifugal, variable, fixed displacement, positive displacement, as nonlimiting examples.

The above embodiments reduce a required boost stage flow/pressure and provide backup flow for critical engine components. The embodiments also reduce fuel filter total flow. This reduces size, weight and horsepower requirements of the boost pump. The embodiments also improve boost stage efficiency, during cruise/low power conditions the difference between delivered flow and maximum will be lowered.

Claim 1:
A fuel system (<NUM>) of an aircraft engine, comprising:
a boost pump (<NUM>) having an input (<NUM>) and an output (<NUM>);
one or more selector valves (<NUM>);
a first component pump (<NUM>) having an input (<NUM>) fluidly coupled to the output (<NUM>) of the boost pump and an output (<NUM>) of the first component pump is configured to direct fuel to a first component (<NUM>) via the one or more selector valves (<NUM>); and
a second component pump (<NUM>) having an input (<NUM>) that is selectively coupled to either the input (<NUM>) or the output (<NUM>) of the boost pump by the one or more selector valves, and an output (<NUM>) of the second component pump is fluidly coupled to a second component (<NUM>) and selectively coupled to the first component by the one or more selector valves.