Method for managing the control of hot fuel

Abstract

A gas turbine engine fuel supply system can include a fuel delivery system, a thermal management system, a fuel manifold, and one or more sensors that identify one or more fuel parameters. A fuel control system adjusts parameters of the fuel based on data received from the sensors.

Description

TECHNICAL FIELD

[0001] The present subject matter relates generally to fuel delivery systems for gas turbine engines. BACKGROUND

[0002] Gas turbine engines generally include a compressor section, a combustor section, and at least one turbine section. The compressor compresses air, which is mixed with fuel and directed to the combustor. The mixture is then ignited, producing hot combustion gases. The combustion gases are directed to the turbine, which extracts energy from the combustion gases to power the compressor and produce useful work to power a load, such as an electrical generator, or to propel an aircraft in flight.

[0003] The properties of the fuel delivered to the combustor can affect the efficiency of the system. Moreover, significant property changes in the fuel can occur during operation, which further complicates fuel delivery and combustion. Accordingly, improvements in controlling fuel delivery for gas turbine engines are desired. BRIEF DESCRIPTION OF DRAWINGS

[0004] Figure 1 is a schematic cross-sectional view of an exemplary gas turbine engine in accordance with various embodiments of the present disclosure.

[0005] Figure 2 An exemplary property table for fuel is shown.

[0006] Figure 3 Another exemplary property table for fuel is shown.

[0007] Figure 4 is a schematic view of a fuel delivery system and other engine components in accordance with embodiments of the present disclosure.

[0008] Figure 5 is a flowchart showing an exemplary method of controlling fuel delivery for a gas turbine engine in accordance with embodiments of the present disclosure.

[0009] Figure 6 is another flowchart showing an exemplary method of controlling fuel delivery for a gas turbine engine in accordance with embodiments of the present disclosure.

[0010] Figure 7 is another flowchart showing an exemplary method of controlling fuel delivery for a gas turbine engine in accordance with embodiments of the present disclosure.

[0011] Figure 8 is another flowchart showing an exemplary method of controlling fuel delivery for a gas turbine engine in accordance with embodiments of the present disclosure.

[0012] Figure 9 is a schematic view of a fuel delivery system and other engine components in accordance with embodiments of the present disclosure.

[0013] Figure 10 is a schematic illustration of a variable pressure nozzle.

[0014] Figure 11 is another flowchart illustrating an example method of controlling fuel delivery of a gas turbine engine, according to embodiments of the present disclosure.

[0015] Figure 12 is another flowchart illustrating an example method of controlling fuel delivery of a gas turbine engine, according to embodiments of the present disclosure.

[0016] Figure 13 is another flowchart illustrating an example method of controlling fuel delivery of a gas turbine engine, according to embodiments of the present disclosure.

[0017] Figure 14 illustrates another example property table for fuel. DETAILED DESCRIPTION

[0018] Reference will now be made in detail to embodiments of the application, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the application, not limitation of the application. In fact, many variations and modifications of the application can be made that fall within the scope of the application. For instance, features from one example can be combined with features from a different example to create a further example. Thus, it should be apparent that the application is not limited to the examples provided herein but can be practiced with the scope and spirit of the application. In the drawings, the same reference numbers signify the same or similar elements.

[0019] The word “exemplary” is used herein to mean “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.

[0020] As used herein, the terms “first,” “second,” and “third” can be used interchangeably to distinguish one component from another and are not meant to signify location or importance of the individual components.

[0021] The terms “forward” and “aft” refer to relative positions within a gas turbine engine or vehicle and refer to the normal operating attitude of the gas turbine engine or vehicle. For example, for a gas turbine engine, forward refers to a position closer to the engine inlet and aft refers to a position closer to the engine nozzle or exhaust.

[0022] The terms “upstream” and “downstream” refer to the relative direction with respect to the flow of fluid in a fluid path. For example, “upstream” refers to the direction from which fluid flows and “downstream” refers to the direction to which fluid flows.

[0023] The terms "coupled," "fixed," "attached to" and the like, mean either a direct coupling, fixation or attachment, or an indirect coupling, fixation or attachment via one or more intermediary components or features, unless specifically stated otherwise herein.

[0024] As used herein, "fluid communication" between two or more elements means a configuration in which fluid can communicate between or among the elements, and does not exclude the possibility of other structures, such as filters, flow meters and / or valves disposed between the elements, which can limit fluid transfer between the elements in at least some circumstances.

[0025] Approximating language is applied to modify any quantitative representation that could possibly vary without resulting in a change in the basic function to which it is directed. Accordingly, a value modified by a term or terms, such as "about" and "substantially," is not limited to the precise value specified. In at least some instances, the approximating language can correspond to the precision of an instrument for measuring the value or the precision of the method or machine for constructing or manufacturing the component and / or system. For example, the approximating language can refer to a margin of error of 1, 2, 4, 10, 15, or 20 percent.

[0026] Herein and throughout the specification and claims, range limitations are combined and interchanged, such ranges are identified and include all the sub-ranges included therein unless context or language indicates otherwise. For example, all ranges disclosed herein are inclusive of the endpoints, and the endpoints are independently combinable with each other.

[0027] Reference is now made to the drawings, wherein like numerals refer to like elements throughout, Figure 1 is a schematic cross-sectional view of a gas turbine engine in accordance with an example embodiment of the present disclosure. More specifically, for Figure 1 Embodiments of the present disclosure, the gas turbine engine is a high-bypass turbofan gas turbine engine 10, referred to herein as "turbofan engine 10." As shown, Figure 1 The turbofan 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 engine 10 includes a fan section 14 and a turbine section 16 disposed downstream from the fan section 14.

[0028] The depicted exemplary turbine engine 16 generally includes a substantially tubular outer casing 18 defining an annular inlet 20. The casing 18 encases, in serial flow relationship: a compressor section including a booster 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 exhaust nozzle section 32. The compressor section, combustion section, turbine section, and exhaust nozzle section together at least partially define a core air flowpath 37 through the turbine engine 16. 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.

[0029] During operation of the turbofan engine 10, a volume of air 58 enters the turbofan 10 through the nacelle 50 and / or an associated inlet 60 of the fan section 14. As the volume of air 58 passes across the fan blades 40, a first portion of the air 58 is directed or channeled into the bypass airflow passage 56 as indicated by arrow 62 and a second portion of the air 58 is directed into the LP compressor 22 as indicated by arrow 64. The ratio between the first portion of air 62 and the second portion of air 64 is commonly referred to as a bypass ratio.

[0030] The pressure of the second portion of air 64 is then increased as it is channeled through the high pressure (HP) compressor 24 and into the combustion section 26 where it is mixed with and combusted with fuel to provide combustion gases 66. The combustion gases 66 are then directed through one or more stages 70 of the HP turbine 28 and into the inlet 78 of the LP turbine 30 where a portion of thermal and / or kinetic energy is extracted from the combustion gases 66.

[0031] The combustion gases 66 are then directed through the jet exhaust nozzle section 32 of the turbine engine 16 to provide propulsive thrust. At the same time, the pressure of the first portion of air 62 is significantly increased as the first portion of air 62 is channeled through the bypass airflow passage 56 before being discharged from the fan nozzle exhaust section 76 of the turbofan 10, also providing propulsive thrust.

[0032] Further, the example turbofan engine 10 includes a fuel delivery system 80 that provides a flow of fuel to the combustion section 26 of the turbofan engine 10. The fuel delivery system 80 generally includes a fuel source 82, a plurality of fuel lines 84, and a fuel pump 86. The fuel source 82 can be, for example, a fuel tank located within a fuselage or one or more wings of an aircraft that includes the turbofan engine 10. Further, the example turbofan engine 10 can include an accessory gear box 88 (which can be driven by, for example, one or more drive members of the HP system of the turbofan engine 10 or the LP system of the turbofan engine 10 that extend through the strut 52). For the illustrated embodiment, the accessory gear box 88 is positioned within the nacelle 50 of the turbofan engine 10, and the fuel pump 86 is coupled to and driven by the accessory gear box 88. Further, one or more of the fuel lines 84 extend from the fuel source 82 to the fuel pump 86, and from the fuel pump 86 to one or more fuel nozzles within the combustion section 26.

[0033] Further, the depicted example turbofan engine 10 further includes a thermal management system 90 and a lubrication oil system 92, as Figure 1 schematically illustrated. The thermal management system 90 can generally be configured to transfer heat from heat sources of the turbofan engine 10 to heat sinks of the turbofan engine 10 using a heat transfer bus through which a heat transfer fluid flows. The lubrication oil system 92 can be configured to provide lubrication oil to one or more bearings or sumps within the turbine 16 to facilitate rotation of one or more components, manage heat of certain components (e.g., bearings), etc.

[0034] However, it should be understood that Figure 1 The depicted example turbofan engine 10 is by way of example only, and in other example embodiments, aspects of the present disclosure can additionally or alternatively be applied to any other suitable gas turbine engine. For example, in other example embodiments, the turbofan engine 10 can include any suitable number of compressors, turbines (e.g., an intermediate turbine in addition to the LP and HP turbines), shafts / spools (e.g., one spool, two spools, three spools), etc. Further, in certain example embodiments, aspects of the present disclosure can also be applied to any other suitable aeronautical gas turbine engine, such as, for example, a ducted engine, a turbojet engine, a turboshaft engine, a turboprop engine, etc. Further, in other example embodiments, the example turbofan engine 10 can not be configured as an aeronautical gas turbine engine, but can be configured as an industrial gas turbine engine (e.g., for power generation), a marine gas turbine engine, etc.

[0035] As described above, the fuel delivery system 80 delivers fuel from a fuel source through a plurality of fuel lines to one or more nozzles within a combustion section. The properties of the fuel when delivered to the nozzles have a significant impact on combustion efficiency. Management of these properties of the fuel can significantly improve stable fuel distribution through the nozzles and engine controllability.

[0036] Gas turbine engines can operate using a variety of fuels. As used herein, the term "jet fuel" refers to any fuel suitable for use in an aircraft turbine engine. Two fuels commonly used in commercial aviation include Jet A and Jet A-l. Figure 2 An exemplary table of properties for a fuel (e.g., fuel analog dodecane) is shown. As Figure 2 shown, the density of the fuel begins to experience a rapid transition above a certain temperature. This can vary depending on the fuel, but in the case of Figure 2 dodecane, the density begins to experience a more rapid transition above about 500°F. As described below, due to this rapid change in density within these fuel temperature ranges, it can be desirable to control the fuel temperature and / or pressure to avoid these transition regions.

[0037] Figure 3 Another exemplary table of properties for a fuel (e.g., fuel analog dodecane) is shown. This table will vary depending on the specific jet fuel, but Figure 3 An exemplary saturation line is shown, which shows at which temperature the fuel will begin to boil. Similarly, Figure 14 An exemplary fuel boiling curve for Jet-A is shown, including an average Jet-A boiling curve and a minimum Jet-A boiling curve. In many cases, it is undesirable for the fuel to boil. For example, as described below, it can be desirable to avoid boiling of the fuel in the manifold and / or fuel nozzles, and in certain embodiments, as described below, the system can adjust the temperature and / or pressure of the fuel to avoid boiling of the fuel.

[0038] In certain embodiments, boiling and other state changes of the fuel can be avoided by adjusting the pressure, temperature, and / or density of the fuel to maintain the fuel in a supercritical state. For example, for the fuel type shown, Figure 3 the supercritical pressure is 263.5 psia and the supercritical temperature is 724.7°.

[0039] In Figure 4 the embodiment shown, a system and method of controlling the phase of a gas turbine fuel is provided. As Figure 4As shown, the fuel delivery system 80 directs fuel to the thermal management system 90. As described above, the thermal management system can be configured to transfer heat from heat sources of the turbofan engine 10 to heat sinks of the turbofan engine 10 using a heat transfer bus through which a heat transfer fluid flows. In particular, in operation, fuel can be passed through one or more heat exchangers 98 of the thermal management system 90 (along a path 99) to increase a temperature of the fuel before the fuel is delivered to a fuel manifold 100, and in turn, to a plurality of nozzles 102 within the combustion section 26.

[0040] As shown, one or more sensors 104 can be provided within one or more locations within the fuel delivery system, fuel path, and / or within the manifold 100. The sensors 104 can provide data indicative of different parameters of the fuel, including, for example, a temperature, pressure, and / or flow rate of the fuel at the location of the sensor 104. Figure 4

[0041] As shown, the fuel control system (controller) 106 can receive data from the one or more sensors 104, with communication schematically illustrated by dashed lines. It should be appreciated that the controller can receive data from other locations and systems as well. Data from the sensors 104 can be used individually to determine fuel parameters, or in certain instances, multiple different sensors 104 at different locations can be used collectively to determine a change in the same fuel parameter within the system. Based on the data received at the controller, the controller can be configured to change a temperature and / or pressure of the fuel. For example, as discussed below, in certain embodiments, the temperature of the fuel can be adjusted by increasing or decreasing heat provided to the fuel (e.g., through one or more heat exchangers of the thermal management system). Additionally or alternatively, the pressure of the fuel can be increased or decreased within the system (e.g., along the flow path of the fuel by one or more pumps and / or at the fuel nozzles by adjusting a differential pressure of the nozzles). Figure 4 Figure 4

[0042] In certain embodiments, the fuel control system 106 can be operably coupled to one or more bypass valves 108, and in response to data received from the sensors 104, the fuel control system 106 can direct fuel to the bypass valves 108 (e.g., along a path 101) such that the fuel bypasses the thermal management system 90 by directing the fuel along paths 101 and 103 to a location downstream of the thermal management system 90.

[0043] In certain embodiments, the fuel control system can be configured to bypass the thermal management system 90 when one or more sensors identify an undesirable fuel condition for fuel distribution to the turbofan engine.

[0044] ​​​In one embodiment, the fuel control system can be configured to respond to the identification of an unwanted temperature of the fuel. For example, the fuel control system can be configured to respond when one or more sensors indicate that the fuel temperature has changed due to a rapid, unwanted change (e.g., as indicated by a rapid, unwanted change in temperature). Figure 2 As shown, when the density change at 500°F exceeds the temperature specified as undesirable, the fuel bypasses the thermal management system.

[0045] The density of jet fuel varies at higher temperatures (for example, for some jet fuels, the temperature is between approximately 500°F and 800°F). Figure 2 This becomes more apparent under certain conditions. Therefore, in some embodiments, the fuel control system can be configured to allow fuel to bypass the thermal management system when the temperature exceeds 500°F, 450°F, 400°F, 350°F, or 300°F. In another embodiment, the fuel control system can be configured to allow fuel to bypass the thermal management system when one or more sensors sense a fuel temperature between 400°F and 600°F. In this way, the temperature of the fuel delivered to the nozzles of the fuel manifold can be maintained within a desired range by the fuel control system and the fuel delivery system communicating with the sensors.

[0046] Therefore, as Figure 5 As shown, a method for controlling the characteristics of fuel delivered to a manifold and / or multiple nozzles may include the steps of: obtaining fuel temperature from one or more sensors 110, comparing the detected temperature with a predetermined maximum temperature 112, and guiding fuel to bypass the thermal management system when the detected temperature exceeds the maximum temperature.

[0047] In another embodiment, Figure 4 The fuel control system 106 shown can be configured to allow fuel to bypass the thermal management system when a minimum fuel density is detected. For example, Figure 5 A method is shown: acquiring temperature and pressure data from one or more sensors (step 120), calculating the fuel density at the sensors based on the data acquired from the one or more sensors (step 122), comparing the calculated density with a minimum permissible density (step 124), and if the calculated density is less than a predetermined minimum permissible density, instructing a fuel bypass valve to open (allowing fuel to bypass the thermal management system) (step 126). In one embodiment, the minimum permissible density is the density at which the fuel density begins to change rapidly at higher temperatures. For example, refer to... Figure 2 The minimum permissible density can be 30 lbm / ft 3 Up to 40 lbm / ft 3 Between, or at 35 lbm / ft 3 Up to 40 lbm / ft 3 Between, for example, approximately 38 lbm / ft 3.

[0048] In certain embodiments, the minimum allowable density can be determined as a percentage of the fuel density at 0°F. For example, in certain cases, the predetermined minimum allowable density is in the range of 70% to 95%, or 80% to 95%, or 80-88% of the fuel density measured at 0°F.

[0049] In another embodiment, Figure 4 The illustrated fuel control system 106 can be configured to bypass the thermal management system based on a combination of the determined temperature Figure 5 ) and density Figure 6 ). Thus, for example, the fuel control system can be configured to open the bypass valve when the temperature exceeds a predetermined temperature and / or the density is below a predetermined density.

[0050] Thus, for example, the fuel control system 106 can be configured to open the bypass valve (or close the bypass valve) when the determined fuel temperature and density fall outside of a desired operating range. Referring to Figure 2 , for example, a desired operating range of about 38 lbm / ft 3 of density can require a temperature of less than about 400°F, or in certain embodiments, less than about 300°F. In other cases, the required operating range can be between about 200°F and 400°F. In the event either parameter falls outside of the desired range, the fuel control system 106 can be configured to open (or close) the bypass valve such that the fuel bypasses (or enters) the thermal management system.

[0051] In certain embodiments, the system can be configured to open the bypass valve until the flight condition is no longer met and / or the fuel temperature is not exceeded, in certain flight conditions and / or if the fuel temperature exceeds a predetermined maximum temperature.

[0052] Figure 7 The above-described method is illustrated, where temperature and pressure data are obtained (step 130), the density of the fuel is determined (step 132), and the obtained temperature information is compared to a predetermined temperature limit and the determined density is compared to a minimum allowable density (step 134). When one or both parameters are outside of a desired operating range discussed herein, the fuel control system 106 causes the fuel to bypass the thermal management system (step 136).

[0053] In another embodiment, Figure 4 The illustrated fuel control system 106 can be configured to bypass the thermal management system when a predetermined change in the density of the fuel is detected. As described above and as Figure 2As shown, the density of the fuel can undergo a rapid transition above a certain temperature (e.g., about 500°F), and identifying a change in density that exceeds a predetermined amount over a certain time period can be an effective method of identifying a transition in fuel properties to an undesirable range.

[0054] Referring to Figure 8 , another method of controlling a property of fuel delivered to a manifold and / or multiple nozzles is provided based on an identification of an undesirable change in density of the fuel. As shown, Figure 8 , this method can include the steps of obtaining temperature and pressure parameters of the fuel from one or more sensors over a predetermined time period (step 140), calculating a change in density over the same time period (step 142), and comparing the change in density to a predetermined maximum allowable change in density over the time period (step 144). If the change in density exceeds the predetermined maximum over the predetermined time period, a fuel bypass valve is directed to open to allow the fuel to bypass the thermal management system (step 146).

[0055] In yet another embodiment, the properties of the fuel can be further altered (in addition or alternatively) by adjusting the pressure of the fuel in the system. For example, the pressure of the fuel within the fuel path can be increased or decreased by controlling one or more pumps accordingly. Alternatively or additionally, the pressure of the fuel at the fuel nozzles can be adjusted by dynamically controlling the fuel nozzles to alter the properties of the fuel at the fuel nozzles.

[0056] Figure 9 Another example system and method of controlling a gas turbine fuel phase is shown. Similar Figure 4 , Figure 9 A fuel delivery system 80 is disclosed that directs fuel to a thermal management system 90 and / or bypasses the thermal management system if a fuel control system opens a bypass valve 108. One or more sensors 104 can be provided in the fuel path (as shown in Figure 4 ) and / or within one or more locations within the manifold 100. The sensors 104 can provide data indicative of the temperature, pressure, and / or flow rate of the fuel at the location of the sensors 104. In this embodiment, the fuel control system 106 is also in communication with one or more pumps and nozzles 102. From the data from the sensors, the fuel control system can additionally alter the pressure of the fuel within the system, or respond by controlling the pumps (e.g., Figure 1 , fuel pumps 86) and / or controlling the nozzles to adjust one or more of the temperature, pressure, and density of the fuel in the nozzles.

[0057] For example, Figure 10An example variable pressure fuel nozzle 149 is shown that can be passively or actively (e.g., by the fuel control system 106) varied to change a fuel parameter at the fuel nozzle. For example, the fuel nozzle can include an exit region 151 that can be increased or decreased by (actively or passively) moving a nozzle adjustment member 153 away from or closer to the nozzle exit region 151.

[0058] In one embodiment, the variable pressure fuel nozzle can decrease or increase the pressure of the fuel to a predetermined range. In this way, the variable pressure fuel nozzle can act to affect the fuel pressure in addition to or separate from a bypass valve. In certain embodiments, the variable fuel nozzle can respond based on a calculated density and / or a calculated change in density as described herein to adjust the pressure to increase or decrease a desired density.

[0059] In another embodiment, the variable fuel nozzle system can be provided by employing a staged plurality of fuel nozzles such that one or more groups of nozzles can be independently controlled. For example, one or more valves can be used to vary the number of fuel nozzles in operation at any time. In this way, the pressure can be decreased by enabling more fuel nozzles at a time or by disabling fuel nozzles.

[0060] For example, similar to the method described in Figure 6 , Figure 11 A method is shown of obtaining temperature and pressure data from one or more sensors (step 150), calculating a density of the fuel at the sensor based on the data obtained by the one or more sensors (step 152), comparing the calculated density to a minimum allowed density (step 154), and if the calculated density is less than the predetermined minimum allowed density, changing the nozzle pressure (e.g., by changing an orifice area of one or more nozzles or changing a number of nozzles enabled) to increase the delivered fuel pressure (step 156). Similarly, if desired, the delivered fuel pressure can be decreased based on the determined condition of the fuel. For example, if the minimum allowed density is 38 lbm / ft 3 , the nozzle can increase the fuel density at the nozzle when one or more sensors of the system detect a minimum allowed density of less than 38 lbm / ft 3 , as shown. The nozzle can be controlled by the fuel control system 106, which can include one or more high frequency (HF) electrical controllers associated therewith. Figure 9

[0061] ​In some embodiments, using an associated HF controller to control the fuel parameters at the nozzle provides additional opportunities for delivering fuel to the nozzle in a desired state. In some embodiments, the desired state of the fuel may be a liquid state as described above to avoid changes in fuel parameters when the fuel boils or enters a gaseous state. However, in other embodiments, the desired state of the fuel may be a supercritical state. For example, a method of delivering fuel in this manner can be achieved by delivering fuel in a supercritical state to the fuel nozzle and adjusting the pressure differential of the fuel nozzle as needed to obtain the desired fuel state and parameters.

[0062] like Figure 12 As shown, in some embodiments, the fuel control system 106 may obtain information about the temperature, pressure, and / or density of the fuel from one or more sensors (step 160), and based on this information, maintain the fuel in a liquid or supercritical state (step 162). To maintain the fuel in a liquid or supercritical state, the fuel control system may modify the fuel pressure and / or temperature. For example, to maintain the fuel in a supercritical state, the fuel control system may maintain the fuel above its supercritical temperature and supercritical pressure. The fuel characteristics can then be compared to desired fuel characteristics (step 164), and fuel dynamics can be managed by increasing the pressure of the fuel along the fuel delivery path, maintaining the fuel in a liquid or supercritical state as needed. In some embodiments, the pressure may be modified by changing the pressure differential at the nozzle as needed (step 166).

[0063] Alternatively, or in addition to changing the pressure differential at the nozzles, the system can increase the pressure of the fuel delivery system 80 to maintain the fuel at the temperature and pressure at which it is in a liquid or supercritical state. Therefore, the fuel pressure can be increased (or decreased) along the fuel path (e.g., by fuel pump 86 or other pumps located at any other point along the delivery system before combustion), including at the nozzles (as in...). Figure 12 (in the middle) to keep the fuel in a liquid or supercritical state.

[0064] Alternatively, or in addition to changing the fuel pressure as described above, the fuel temperature can be changed as needed to maintain the fuel in a liquid or supercritical state. For example, as mentioned above... Figure 4 As described, fuel can bypass the thermal management system when the detected temperature exceeds a maximum temperature. In some embodiments, alternatively, or in addition to bypassing the thermal management system, the system can control the heat input / output of the thermal management system to alter the heat transferred to the fuel engaged with the thermal management system. Thus, for example, when a maximum desired temperature is reached, the controller can cause fuel to bypass the thermal management system and / or the controller can reduce the heat transferred to the fuel engaged with the thermal management system (e.g., by reducing the heat input to one or more heat exchangers 98).

[0065] Figure 13 An example system is shown that can obtain information about the temperature, pressure, and / or density of the fuel from one or more sensors (step 168) and, based on that information, maintain the fuel in a liquid or supercritical state (step 170). For example, to maintain the fuel in a liquid or supercritical state, the fuel control system can control the heat delivered to the fuel based on a comparison of the information received by the sensors to the desired properties of the fuel to maintain the fuel in a liquid or supercritical state.

[0066] As described herein, modifications to the fuel based on temperature, pressure, and / or density can similarly be implemented using calculations of variables that are closely related to those variables. For example, as the temperature of the fuel changes, the modulus of elasticity also changes similarly. Thus, fuel properties can also be modified based on a calculated modulus of elasticity of the fuel and / or a change in the calculated modulus of elasticity, including a determination of the temperature of the fuel. Similarly, other parameters derived from temperature, pressure, and / or density can be used to control modifications to the fuel, as described herein. For example, instead of (or in addition to) temperature, pressure, and / or density, a determination of kinematic viscosity, viscosity, volume flow, and specific volume can be used to identify a change in the state of the fuel or an approximation of a change in the state of the fuel. Thus, for example, a decrease in viscosity can indicate a change in the fuel from a liquid state to a gaseous state. Thus, such a change can be determined by a controller (e.g., through one or more sensors and / or one or more calculations) and more or less heat can be provided to the fuel to maintain the fuel in a desired state (e.g., liquid, supercritical).

[0067] In certain embodiments, detection of a change in the desired value of a parameter and / or the amount of change in the current operating value by the controller can be used to detect a change in the state of the fuel (e.g., a change from a liquid state to a gaseous state). For example, in certain embodiments, a determination of a change of 5% or more (e.g., 5%-10%, 5%-20%) in the desired or current operating conditions relative to any one or more variables (depending on the increase or decrease in the variable and the desired state of the fuel) can cause the controller to increase or decrease the heat provided to the fuel: temperature, pressure, modulus of elasticity, kinematic viscosity, viscosity, volume flow, and / or specific volume. For example, a 5% increase in fuel temperature can cause the controller to decrease the heat supplied to the fuel to maintain the fuel in a liquid state. In another embodiment, a 5% decrease in fuel temperature can cause the controller to increase the heat supplied to the fuel to maintain the fuel in a supercritical state. Similarly, a 5% decrease in viscosity can cause the controller to decrease the heat supplied to the fuel to maintain the fuel in a liquid state, while a 5% increase in viscosity can cause the controller to increase the heat supplied to the fuel to maintain the fuel in a supercritical state.

[0068] In certain embodiments, the nozzle flow number FN can be determined by the following equation where WF is the fuel flow through the nozzle, P fuel is the fuel manifold pressure, and P3 is the combustion chamber pressure. Changes in FN can be used to identify changes in fuel state. For example, in certain embodiments, a determination of a change of 5% or more (e.g., 5%-10%, 5%-20%) in FN relative to a desired or current operation can indicate a change in fuel state (or an approximate change in fuel state) and the controller can be configured to increase or decrease the heat of the supplied fuel to adjust the fuel temperature, as described herein.

[0069] Suitable controllers that can direct the system to increase or decrease temperature, pressure, or other variables based on feedback from various sensors are described in more detail below.

[0070] As described above, the fuel control system 106 can obtain temperature and pressure data of the fuel from one or more sensors (e.g., step 160) and, based on this information, maintain the fuel in a liquid state. For example, with reference to Figure 14 At pressures above 150 psi, the temperature of the fuel can be maintained below 550°F to avoid boiling of the fuel in the manifold and / or nozzle. In certain embodiments, a temperature and pressure table can be stored by the fuel control system 106 and compared to the temperature and pressure obtained by one or more sensors to determine whether the temperature and / or pressure should be decreased or increased to avoid boiling of the fuel. In certain embodiments, the maximum temperature and pressure can be values selected to be below the boiling point of the fuel, such as values at least 1% below the boiling point and / or pressure of the fuel, or in certain embodiments, 1% to 10% below the boiling point and / or pressure of the fuel.

[0071] Generally, the fuel control system 106 can include one or more processor-based devices, such as a given controller or computing device, or any suitable combination of controllers or computing devices. Thus, in several embodiments, the fuel control system 106 can include one or more processors and associated memory devices configured to perform a variety of computer-implemented functions. As used herein, the term "processor" refers not only to integrated circuits designed for this purpose, but also includes a controller, microcontroller, microcomputer, programmable logic circuit (PLC), application specific integrated circuit, and other programmable circuitry. Additionally, the memory devices of the computing system can generally include memory elements, including but not limited to computer-readable media, for example, random access memory (RAM), computer-readable non-volatile media, for example, flash memory, floppy drive disks, optical disks, Compact Disc Read Only Memory (CD-ROM), magneto-optical disks, Digital Versatile Discs (DVD), and / or other suitable memory elements. Such memory devices are typically configured to store suitable computer-readable instructions, which, when implemented by the processor, configure the fuel control system 106 to perform various computer-implemented functions, such as one or more aspects of the methods and algorithms described herein. Moreover, the fuel control system 106 can also include various other suitable components, such as communication circuitry or modules, one or more input / output channels, data / control buses, etc.

[0072] In certain embodiments, as described above, the fuel control system 106 is configured to receive data from various sensors to monitor, for example, the temperature, pressure, and / or flow rate of the fuel. More specifically, during operation of the fuel delivery system, the fuel control system 106 is configured to receive data captured by the sensors 104 (e.g., via the communication links indicated by dashed lines). The fuel control system 106 is configured to process / analyze the received sensor data to determine and / or calculate values that the system can in turn use to direct other actions, such as opening / closing a bypass valve or adjusting the fuel flow through the nozzle 150. For example, the fuel control system 106 can include a suitable lookup table stored within its memory devices that respectively associates data received from the sensors and / or data calculated from the sensor data with one or more required adjustments to the fuel delivery based on the received data. For example, the lookup table can include boiling curve information (e.g., as shown in Figure 14 Figure 3

[0073] Further aspects of the present application are provided by the subject matter of the following clauses:

[0074] ​​1. A gas turbine engine fuel supply system comprising: a fuel delivery system including a fuel source, a plurality of fuel lines, and at least one fuel pump; a thermal management system including at least one heat exchanger engaged with a first portion of the plurality of fuel lines and configured to increase a temperature of the fuel in the first portion of the plurality of fuel lines; a fuel manifold downstream of the thermal management system and in fluid communication with a second portion of the plurality of fuel lines, the first portion and the second portion in fluid communication; one or more sensors positioned within the fuel manifold and / or the second portion of the plurality of fuel lines, the one or more sensors configured to identify one or more fuel parameters; a bypass system including one or more valves upstream of the first portion of the plurality of fuel lines and a third portion of the plurality of fuel lines that bypasses the thermal management system, the third portion of the plurality of fuel lines in fluid communication with the second portion of the plurality of fuel lines; and a fuel control system configured to receive data indicative of the one or more fuel parameters and send a signal to the bypass system to open or close the one or more valves of the bypass system based on the data received from the one or more sensors.

[0075] 2. The gas turbine engine fuel supply system of clause 1, wherein the one or more sensors include a temperature sensor and the fuel parameter includes a temperature of the fuel, and wherein the fuel control system is configured to compare the fuel temperature from the one or more sensors to a predetermined maximum temperature and send a signal to the bypass system to open the one or more valves and direct fuel into the bypass system when the temperature of the fuel from the one or more sensors exceeds the predetermined maximum temperature.

[0076] 3. The gas turbine engine fuel supply system of clause 2, wherein the predetermined maximum temperature of the fuel is between 300°F and 600°F.

[0077] 4. The gas turbine engine fuel supply system of any preceding clause, wherein the one or more sensors comprise a temperature sensor and a pressure sensor, and the fuel parameters comprise a temperature and a pressure of the fuel, and wherein the fuel control system is configured to calculate a density of the fuel based on the fuel parameters received from the one or more sensors, compare the calculated density to a predetermined minimum allowable density, and send a signal to the bypass system to open the one or more valves and direct fuel into the bypass system when the calculated density of the fuel is less than the predetermined minimum allowable density.

[0078] 5. The gas turbine engine fuel supply system of clause 4, wherein the predetermined minimum allowable density is between 70% and 95% of the density of the fuel measured at 0°F.

[0079] 6. The gas turbine engine fuel supply system of clause 4, wherein the predetermined minimum allowable density is between 80% and 88% of the density of the fuel measured at 0°F.

[0080] 7. The gas turbine engine fuel supply system of clause 4, wherein the one or more sensors comprise a temperature sensor and a pressure sensor, and the fuel parameters comprise a temperature and a pressure of the fuel, and wherein the fuel control system is configured to calculate a change in fuel density based on the fuel parameters received from the one or more sensors over a predetermined time period, compare the change in density to a predetermined maximum allowable change in density, and send a signal to the bypass system to open the one or more valves and direct fuel into the bypass system when the calculated change in the density of the fuel exceeds the predetermined maximum allowable change in density.

[0081] 8. A gas turbine engine fuel supply system comprising: a fuel delivery system including a fuel source, a plurality of fuel lines, and at least one fuel pump; a thermal management system including at least one heat exchanger engaged with a first portion of the plurality of fuel lines and configured to increase a temperature of the fuel in the first portion of the plurality of fuel lines; a fuel manifold downstream of the thermal management system and in fluid communication with a second portion of the plurality of fuel lines, the first portion and the second portion in fluid communication; one or more sensors positioned within the fuel manifold and / or second portion of the plurality of fuel lines, the one or more sensors configured to identify one or more fuel parameters; a bypass system including one or more valves upstream of the first portion of the plurality of fuel lines and a third portion of the plurality of fuel lines that bypasses the thermal management system, the third portion of the plurality of fuel lines in fluid communication with the second portion of the plurality of fuel lines; and a fuel control system configured to receive data indicative of the one or more fuel parameters and send a signal to the thermal management system to increase or decrease an amount of heat transferred to the fuel based on the data received from the one or more sensors.

[0082] 9. The gas turbine engine fuel supply system of clause 8, further comprising: a bypass system including one or more valves upstream of the first portion of the plurality of fuel lines and a third portion of the plurality of fuel lines that bypasses the thermal management system, the third portion of the plurality of fuel lines in fluid communication with the second portion of the plurality of fuel lines, wherein a controller of the fuel control system is configured to send a signal to the bypass system to open or close the one or more valves of the bypass system based on data received from the one or more sensors.

[0083] 10. The gas turbine engine fuel supply system of clause 8, wherein a controller of the fuel control system is configured to send a signal to the at least one heat exchanger to vary an amount of heat transferred to fuel passing through the at least one heat exchanger.

[0084] 11. The gas turbine engine fuel supply system of clause 8, wherein the one or more sensors include a temperature sensor and the fuel parameter includes a temperature of the fuel, and wherein the fuel control system is configured to compare the temperature of the fuel from the one or more sensors to a predetermined maximum temperature and, when the temperature of the fuel exceeds the predetermined maximum temperature, the controller sends a signal to decrease an amount of heat transferred to the fuel.

[0085] 12. The gas turbine engine fuel supply system of clause 11, wherein the predetermined maximum temperature of the fuel is between 300°F and 600°F.

[0086] 13. The gas turbine engine fuel supply system of clause 8, wherein the one or more sensors include a temperature sensor and a pressure sensor, and the fuel parameters include a temperature and a pressure of the fuel, and wherein the fuel control system is configured to calculate a density of the fuel based on the fuel parameters received from the one or more sensors, compare the calculated density to a predetermined minimum allowed density, and send a signal to reduce heat transferred to the fuel when the calculated density of the fuel is less than the predetermined minimum allowed density.

[0087] 14. The gas turbine engine fuel supply system of clause 13, wherein the predetermined minimum allowed density is between 70% and 95% of the density of the fuel measured at 0°F.

[0088] 15. The gas turbine engine fuel supply system of clause 13, wherein the predetermined minimum allowed density is between 80% and 88% of the density of the fuel measured at 0°F.

[0089] 16. The gas turbine engine fuel supply system of clause 8, wherein the one or more sensors include a temperature sensor and a pressure sensor, and the fuel parameters include a temperature and a pressure of the fuel, and wherein the fuel control system is configured to calculate a change in density of the fuel based on the fuel parameters received from the one or more sensors over a predetermined time period, compare the change in density to a predetermined maximum allowed change in density, and send a signal to reduce heat transferred to the fuel when the calculated change in density of the fuel is greater than the predetermined maximum allowed change in density.

[0090] 17. The gas turbine engine fuel supply system of clause 8, wherein the one or more sensors include a temperature sensor and a pressure sensor, and the fuel parameters include a temperature and a pressure of the fuel, and wherein the fuel control system is configured to maintain the fuel at a temperature and pressure below a boiling point of the fuel to avoid boiling of the fuel by receiving the temperature and pressure of the fuel from the one or more sensors over a predetermined time period and comparing the received temperature and pressure to a predetermined boiling point table, and changing the temperature or pressure of the fuel.

[0091] 18. A gas turbine engine fuel supply system comprising: a fuel delivery system including a fuel source, a plurality of fuel lines, and at least one fuel pump; a thermal management system including at least one heat exchanger engaged with a first portion of the plurality of fuel lines and configured to increase a temperature of the fuel in the first portion of the plurality of fuel lines; a fuel manifold downstream of the thermal management system and in fluid communication with a second portion of the plurality of fuel lines, the first portion and the second portion in fluid communication; a plurality of variable pressure nozzles in fluid communication with the fuel manifold; one or more sensors positioned within the fuel manifold, the second portion of the plurality of fuel lines, and / or the variable pressure nozzles, the one or more sensors including at least one temperature sensor and at least one pressure sensor, the at least one temperature sensor and the at least one pressure sensor identifying a temperature and a pressure of fuel, respectively; and a fuel control system configured to: receive data indicative of the temperature and pressure of the fuel from the one or more sensors, and adjust the temperature and / or pressure of the fuel based on the received data.

[0092] 19. The gas turbine engine fuel supply system of clause 18, wherein the fuel control system is configured to: determine whether fuel is in a supercritical state; and change the temperature and / or pressure of the fuel to maintain the fuel in the supercritical state.

[0093] 20. The gas turbine engine fuel supply system of clause 19, wherein the fuel control system is configured to: if it is determined that the fuel is not in a supercritical state, send a first signal to the thermal management system to increase the temperature of the fuel in the first portion.

[0094] 21. The gas turbine engine fuel supply system of clause 18, wherein the fuel control system is configured to: compare the temperature and pressure of the fuel to predetermined operable temperatures and pressures; and if it is determined that the fuel is not in a supercritical state, send a second signal to increase or decrease the pressure of the fuel.

[0095] 22. The gas turbine engine fuel supply system of clause 21, wherein the second signal directs the plurality of variable pressure nozzles to increase or decrease a differential pressure of the plurality of variable pressure nozzles based on the comparison.

[0096] 23. The gas turbine engine fuel supply system of Clause 21, wherein the second signal directs the at least one fuel pump to increase or decrease the pressure of the fuel in the fuel line based on the comparison.

[0097] 24. The gas turbine engine fuel supply system of Clause 18, wherein the fuel control system is configured to, if it is determined that the fuel is not in a supercritical state, send a first signal to the thermal management system to increase the temperature of the fuel in the first portion, compare the temperature and pressure of the fuel to predetermined operable temperatures and pressures, and based on the comparison, send a second signal to the plurality of variable pressure nozzles to increase or decrease the differential pressure of the plurality of variable pressure nozzles.

[0098] 25. The gas turbine engine fuel supply system of Clause 25, wherein the fuel control system is configured to determine whether the fuel is in a liquid state, and to change the temperature and / or pressure of the fuel to maintain the fuel in the liquid state.

[0099] 26. The gas turbine engine fuel supply system of Clause 25, wherein the fuel control system is configured to compare the temperature of the fuel to a predetermined maximum allowable temperature, and when the temperature of the fuel is above the predetermined maximum allowable temperature, send a signal to a bypass system to open one or more valves and direct fuel into the bypass system.

[0100] 27. The gas turbine engine fuel supply system of Clause 25, wherein the fuel control system is configured to compare the temperature and pressure of the fuel to predetermined boiling point data, and to adjust the temperature and / or pressure of the fuel to maintain the fuel at a temperature and pressure below the boiling curve of the fuel.

[0101] 28. The gas turbine engine fuel supply system of Clause 25, wherein the fuel control system is configured to calculate a density of the fuel based on the fuel parameters received from the one or more sensors, compare the calculated density to a predetermined minimum allowable density, and when the calculated density of the fuel is less than the predetermined minimum allowable density, send a signal to a bypass system to open one or more valves and direct fuel into the bypass system.

[0102] 29. The gas turbine engine fuel supply system of Clause 28, wherein the predetermined minimum allowable density is between 70% and 95% of the density of the fuel measured at 0°F.

[0103] 30. The gas turbine engine fuel supply system of Clause 28, wherein the predetermined minimum allowable density is between 80% and 88% of the density of the fuel measured at 0°F.

[0104] 31. A method of controlling a fuel supply system of a gas turbine engine of an aircraft, comprising delivering jet fuel from a fuel source through one or more pumps through a plurality of fuel lines; determining one or more fuel parameters by obtaining data from one or more sensors located within one or more locations of a fuel manifold and / or the plurality of fuel lines; and adjusting a temperature and / or pressure of the fuel based on the determined fuel parameters to maintain the fuel in a liquid or supercritical state.

[0105] 32. The method of Clause 31, wherein the one or more sensors comprise a temperature sensor and the one or more fuel parameters comprise the temperature of the fuel.

[0106] 33. The method of Clause 31 or 32, wherein the one or more sensors comprise a pressure sensor and the one or more fuel parameters comprise the pressure of the fuel.

[0107] 34. The method of any of Clauses 31-33, wherein adjusting the temperature or pressure of the fuel comprises opening one or more valves to bypass at least one heat exchanger of a thermal management system.

[0108] 35. The method of any of Clauses 31-34, wherein adjusting the temperature or pressure of the fuel comprises adjusting an amount of heat supplied to the fuel by at least one heat exchanger of a thermal management system.

[0109] 36. The method of any of Clauses 31-35, wherein adjusting the temperature or pressure of the fuel comprises adjusting a pressure of the fuel by changing a pump pressure and / or adjusting a pressure at a nozzle system.

[0110] 37. The method of any of Clauses 31-36, wherein the one or more fuel parameters comprise one or more of a pressure, a temperature, a density, a modulus of elasticity, a kinematic viscosity, a viscosity, a volumetric flow rate, and a specific volume.

[0111] 38. The method of Clause 37, further comprising determining a percent change of the one or more fuel parameters, and adjusting the temperature and / or pressure of the fuel if the percent change is 5% or greater.

[0112] 39. The method of any of clauses 31-36, further comprising determining a percent change in the nozzle flow value, and adjusting the temperature and / or pressure of the fuel if the percent change is 5% or greater.

[0113] 40. The method of clause 31, wherein the one or more sensors provide data sufficient to determine the fuel parameter.

[0114] 41. The method of clause 40, wherein the fuel parameter comprises at least one of a modulus of elasticity, a nozzle flow value, a kinematic viscosity, a viscosity, a volumetric flow, and a specific volume.

[0115] 42. The method of any of clauses 40-41, wherein the fuel parameter is calculated from the data provided by the one or more sensors.

[0116] 43. The method of clause 42, wherein the fuel parameter is calculated using a lookup table.

[0117] In view of the many possible embodiments to which the principles of the disclosed application can be applied, it should be recognized that the examples described herein are only preferred examples of the application and should not be considered limiting the scope of the application. Rather, the scope of the application is defined by the following claims. Therefore, we claim all that comes within the scope and spirit of these claims.

Claims

1. A fuel supply system for a gas turbine engine, characterized in that, include: A fuel delivery system, comprising a fuel source, multiple fuel pipelines, and at least one fuel pump; A thermal management system comprising at least one heat exchanger, the at least one heat exchanger being engaged with a first portion of the plurality of fuel lines and configured to increase the temperature of the fuel in the first portion of the plurality of fuel lines; A fuel manifold located downstream of the thermal management system and in fluid communication with a second portion of the plurality of fuel lines, wherein the first and second portions are in fluid communication. One or more sensors, located within the second portion of the fuel manifold and / or the plurality of fuel lines, the one or more sensors being configured to identify one or more fuel parameters; A bypass system comprising one or more valves located upstream of a first portion of the plurality of fuel lines and a third portion of the plurality of fuel lines bypassing the thermal management system, the third portion of the plurality of fuel lines being in fluid communication with the second portion of the plurality of fuel lines; and A fuel control system configured to receive data indicating one or more fuel parameters and, based on data received from the one or more sensors, send signals to the bypass system to open or close the one or more valves of the bypass system. The fuel control system is further configured to change the pressure difference of the multiple variable pressure nozzles by controlling multiple variable pressure nozzles, thereby increasing the pressure of the fuel and maintaining the fuel in a supercritical state.

2. The gas turbine engine fuel supply system according to claim 1, characterized in that, in, The one or more sensors include a temperature sensor, and the fuel parameter includes the temperature of the fuel. The fuel control system is configured to compare the temperature of the fuel from the one or more sensors with a predetermined maximum temperature, and when the temperature of the fuel from the one or more sensors exceeds the predetermined maximum temperature, to send a signal to the bypass system to open the one or more valves and direct the fuel into the bypass system.

3. The gas turbine engine fuel supply system according to claim 2, characterized in that, in, The predetermined maximum temperature of the fuel is between 300°F and 600°F.

4. The gas turbine engine fuel supply system according to claim 1, characterized in that, in, The one or more sensors include a temperature sensor and a pressure sensor, and the fuel parameters include the temperature and pressure of the fuel. The fuel control system is configured as follows: The density of the fuel is calculated based on the fuel parameters received from the one or more sensors. The calculated density is compared with the predetermined minimum allowable density, and When the calculated density of the fuel is less than the predetermined minimum allowable density, a signal is sent to the bypass system to open one or more valves and direct the fuel into the bypass system.

5. The gas turbine engine fuel supply system according to claim 4, characterized in that, in, The predetermined minimum permissible density is between 70% and 95% of the density of the fuel measured at 0°F.

6. The gas turbine engine fuel supply system according to claim 4, characterized in that, in, The predetermined minimum permissible density is between 80% and 88% of the density of the fuel measured at 0°F.

7. The gas turbine engine fuel supply system according to claim 1, characterized in that, in, The one or more sensors include a temperature sensor and a pressure sensor, and the fuel parameters include the temperature and pressure of the fuel. The fuel control system is configured as follows: The density change of the fuel is calculated based on the fuel parameters received from the one or more sensors within a predetermined time period. The density change is compared with a predetermined maximum permissible density change, and When the calculated density change of the fuel exceeds the predetermined maximum allowable density change, a signal is sent to the bypass system to open one or more valves and direct the fuel into the bypass system.

8. A fuel supply system for a gas turbine engine, characterized in that, include: A fuel delivery system, comprising a fuel source, multiple fuel pipelines, and at least one fuel pump; A thermal management system comprising at least one heat exchanger, the at least one heat exchanger being engaged with a first portion of the plurality of fuel lines and configured to increase the temperature of the fuel in the first portion of the plurality of fuel lines; A fuel manifold located downstream of the thermal management system and in fluid communication with a second portion of the plurality of fuel lines, wherein the first and second portions are in fluid communication. One or more sensors, located within a second portion of the fuel manifold and / or the plurality of fuel lines, are configured to identify one or more fuel parameters; and A fuel control system configured to receive data indicating one or more fuel parameters and, based on data received from the one or more sensors, send signals to the thermal management system to increase or decrease the heat transferred to the fuel. The one or more sensors include a temperature sensor and a pressure sensor, and the fuel parameters include the temperature and pressure of the fuel. The fuel control system is configured to increase the heat transferred to the fuel and / or increase the pressure of the fuel to maintain the fuel in a supercritical state. The fuel control system is further configured to change the pressure difference of the plurality of variable pressure nozzles by controlling the plurality of variable pressure nozzles, thereby increasing the pressure of the fuel and maintaining the fuel in the supercritical state.

9. The gas turbine engine fuel supply system according to claim 8, characterized in that, Further includes: A bypass system comprising one or more valves located upstream of a first portion of the plurality of fuel lines and a third portion of the plurality of fuel lines bypassing the thermal management system, the third portion of the plurality of fuel lines being in fluid communication with the second portion of the plurality of fuel lines. The controller of the fuel control system is configured to send signals to the bypass system based on data received from the one or more sensors to open or close the one or more valves of the bypass system.

10. The gas turbine engine fuel supply system according to claim 8, characterized in that, in, The controller of the fuel control system is configured to send a signal to the at least one heat exchanger to change the heat transferred to the fuel passing through the at least one heat exchanger.

11. The gas turbine engine fuel supply system according to claim 8, characterized in that, The fuel control system is configured to compare the temperature of the fuel from the one or more sensors with a predetermined maximum temperature, and when the temperature of the fuel exceeds the predetermined maximum temperature, the controller sends a signal to reduce the heat transferred to the fuel.

12. The gas turbine engine fuel supply system according to claim 11, characterized in that, in, The predetermined maximum temperature of the fuel is between 300°F and 600°F.

13. The gas turbine engine fuel supply system according to claim 8, characterized in that, The fuel control system is configured as follows: The density of the fuel is calculated based on the fuel parameters received from the one or more sensors. The calculated density is compared with the predetermined minimum allowable density, and When the calculated density of the fuel is less than the predetermined minimum allowable density, a signal is sent to reduce the heat transferred to the fuel.

14. The gas turbine engine fuel supply system according to claim 13, characterized in that, in, The predetermined minimum permissible density is between 70% and 95% of the density of the fuel measured at 0°F.

15. The gas turbine engine fuel supply system according to claim 13, characterized in that, in, The predetermined minimum permissible density is between 80% and 88% of the density of the fuel measured at 0°F.

16. The gas turbine engine fuel supply system according to claim 8, characterized in that, The fuel control system is configured as follows: The density change of the fuel is calculated based on the fuel parameters received from the one or more sensors within a predetermined time period. The density change is compared with a predetermined maximum permissible density change, and When the calculated density change of the fuel exceeds the predetermined maximum allowable density change, a signal is sent to reduce the heat transferred to the fuel.

17. The gas turbine engine fuel supply system according to claim 8, characterized in that, The fuel control system is configured to maintain the fuel at a temperature and pressure below its boiling point by receiving the temperature and pressure of the fuel from one or more sensors over a predetermined time period, comparing the received temperature and pressure with a predetermined boiling point table, and changing the temperature or pressure of the fuel, so as to avoid the fuel boiling.

18. The gas turbine engine fuel supply system according to claim 8, characterized in that, in, The fuel control system is configured to reduce the heat transferred to the fuel and / or reduce the pressure of the fuel in order to keep the fuel in a liquid state.

19. The gas turbine engine fuel supply system according to claim 8, characterized in that, in, The heat transferred to the fuel is increased or decreased based on data received from the one or more sensors to maintain the fuel in a liquid or supercritical state.

20. A fuel supply system for a gas turbine engine, characterized in that, include: A fuel delivery system, comprising a fuel source, multiple fuel pipelines, and at least one fuel pump; A thermal management system comprising at least one heat exchanger, the at least one heat exchanger being engaged with a first portion of the plurality of fuel lines and configured to increase the temperature of the fuel in the first portion of the plurality of fuel lines; A fuel manifold located downstream of the thermal management system and in fluid communication with a second portion of the plurality of fuel lines, wherein the first and second portions are in fluid communication. Multiple variable pressure nozzles, wherein the multiple variable pressure nozzles are in fluid communication with the fuel manifold; One or more sensors, located within the fuel manifold, the second portion of the plurality of fuel lines, and / or the variable pressure nozzle, the one or more sensors including at least one temperature sensor and at least one pressure sensor, the at least one temperature sensor and the at least one pressure sensor identifying the temperature and pressure of the fuel, respectively; and Fuel control system, the fuel control system being configured to: Data indicating the temperature and pressure of the fuel are received from the one or more sensors, and Adjust the temperature and / or pressure of the fuel based on the received data. The fuel control system is configured to increase the heat transferred to the fuel and / or increase the pressure of the fuel to maintain the fuel in a supercritical state. The fuel control system is further configured to change the pressure difference of the plurality of variable pressure nozzles by controlling the plurality of variable pressure nozzles, thereby increasing the pressure of the fuel and maintaining the fuel in the supercritical state.

21. The gas turbine engine fuel supply system according to claim 20, characterized in that, in, The fuel control system is configured as follows: Determine whether the fuel is in a supercritical state; and The temperature and / or pressure of the fuel are changed to maintain the fuel in the supercritical state.

22. The gas turbine engine fuel supply system according to claim 21, characterized in that, in, The fuel control system is configured as follows: If it is determined that the fuel is not in a supercritical state, a first signal is sent to the thermal management system to increase the temperature of the fuel in the first part.

23. The gas turbine engine fuel supply system according to claim 20, characterized in that, in, The fuel control system is configured as follows: The temperature and pressure of the fuel are compared with a predetermined operable temperature and pressure; and If it is determined that the fuel is not in a supercritical state, a second signal is sent to increase or decrease the pressure of the fuel.

24. The gas turbine engine fuel supply system according to claim 23, characterized in that, in, The second signal guides the plurality of variable pressure nozzles to increase or decrease the pressure difference of the plurality of variable pressure nozzles based on the comparison.

25. The gas turbine engine fuel supply system according to claim 23, characterized in that, in, The second signal directs the at least one fuel pump to increase or decrease the pressure of the fuel in the fuel line based on the comparison.

26. The gas turbine engine fuel supply system according to claim 20, characterized in that, in, The fuel control system is configured as follows: If it is determined that the fuel is not in a supercritical state, a first signal is sent to the thermal management system to increase the temperature of the fuel in the first part; The temperature and pressure of the fuel are compared with a predetermined operable temperature and pressure; and Based on the comparison, a second signal is sent to the plurality of variable pressure nozzles to increase or decrease the pressure difference of the plurality of variable pressure nozzles.

27. The gas turbine engine fuel supply system according to claim 20, characterized in that, in, The fuel control system is configured as follows: Determine whether the fuel is in a liquid state; and The temperature and / or pressure of the fuel are changed to maintain the fuel in the liquid state.

28. The gas turbine engine fuel supply system according to claim 27, characterized in that, in, The fuel control system is configured as follows: The temperature of the fuel is compared with a predetermined maximum permissible temperature, and When the temperature of the fuel is higher than the predetermined maximum allowable temperature, a signal is sent to the bypass system to open one or more valves and direct the fuel into the bypass system.

29. The gas turbine engine fuel supply system according to claim 27, characterized in that, in, The fuel control system is configured as follows: The temperature and pressure of the fuel are compared with predetermined boiling point data, and The temperature and / or pressure of the fuel are adjusted to maintain the fuel at a temperature and pressure below the boiling profile of the fuel.

30. The gas turbine engine fuel supply system according to claim 20, characterized in that, in, The fuel control system is configured as follows: The density of the fuel is calculated based on the fuel parameters received from the one or more sensors. The calculated density is compared with the predetermined minimum allowable density, and When the calculated density of the fuel is less than the predetermined minimum permissible density, a signal is sent to the bypass system to open one or more valves and direct the fuel into the bypass system.

31. The gas turbine engine fuel supply system according to claim 30, characterized in that, in, The predetermined minimum permissible density is between 70% and 95% of the density of the fuel measured at 0°F.

32. The gas turbine engine fuel supply system according to claim 30, characterized in that, in, The predetermined minimum permissible density is between 80% and 88% of the density of the fuel measured at 0°F.

33. A method for controlling the fuel supply system of a gas turbine engine in an aircraft, characterized in that, include: Jet fuel is delivered from the fuel source through one or more pumps and multiple fuel lines; One or more fuel parameters are determined by obtaining data from one or more sensors located at one or more locations in the fuel manifold and / or the plurality of fuel lines; and Based on the determined fuel parameters, the temperature and / or pressure of the fuel are adjusted to maintain the fuel in a liquid or supercritical state. The fuel control system is configured to maintain the fuel in a supercritical state by controlling a plurality of variable pressure nozzles to change the pressure difference of the plurality of variable pressure nozzles.

34. The method according to claim 33, characterized in that, in, The one or more sensors include a temperature sensor, and the one or more fuel parameters include the temperature of the fuel.

35. The method according to claim 33, characterized in that, in, The one or more sensors include a pressure sensor, and the one or more fuel parameters include the pressure of the fuel.

36. The method according to claim 33, characterized in that, in, Regulating the temperature or pressure of the fuel includes opening one or more valves to bypass at least one heat exchanger of the thermal management system.

37. The method according to claim 33, characterized in that, in, Regulating the temperature or pressure of the fuel includes regulating the heat supplied to the fuel by at least one heat exchanger of the thermal management system.

38. The method according to claim 33, characterized in that, in, Adjusting the temperature or pressure of the fuel includes adjusting the pressure of the fuel by changing the pump pressure and / or adjusting the pressure at the nozzle system.

39. The method according to claim 33, characterized in that, in, The one or more fuel parameters include one or more of the following: fuel pressure, temperature, density, elastic modulus, kinematic viscosity, viscosity, volumetric flow rate, and a specific volume.

Images