An aircraft fuel heat sink cooling management system

Abstract

The application belongs to the technical field of aircraft fuel heat sink cooling pipe control design, and particularly relates to an aircraft fuel heat sink cooling pipe control system, which considers the cooling capacity requirements of cooling liquid, hydraulic oil and lubricating oil, designs a variable frequency heat dissipation pump to supply oil pipes, and part of the fuel extracted by the oil pipes flows through a first pipe control branch, a fuel-cooling liquid heat exchanger, a fuel-hydraulic oil heat exchanger and a fuel-lubricating oil heat exchanger to return to the oil supply pipes, part of the fuel flows through a second pipe control branch, a fuel-hydraulic oil heat exchanger and a fuel-lubricating oil heat exchanger to return to the oil supply pipes, and part of the fuel flows through a third pipe control branch, a fuel-lubricating oil heat exchanger to return to the oil supply pipes, so that the fuel can be flexibly and on-demand allocated to efficiently cool the cooling liquid, the hydraulic oil and the lubricating oil, the maximum heat absorption capacity of the fuel heat sink can be efficiently utilized, and waste of the heat sink is avoided.

Description

Technical Field

[0001] This application belongs to the field of aircraft fuel heat sink cooling control design technology, specifically relating to an aircraft fuel heat sink cooling control system. Background Technology

[0002] On aircraft, a portion of the fuel is drawn from the fuel supply line and fed into heat exchange devices such as fuel-cooled liquid heat exchangers, fuel-hydraulic oil heat exchangers, and fuel-lubricating oil heat exchangers. The fuel heat sink absorbs heat to cool the coolant, hydraulic oil, lubricating oil, and other heat-generating media, absorbing the heat generated by the airborne equipment to prevent heat accumulation and enable the airborne equipment to operate efficiently and continuously. The fuel is then returned to the fuel supply line to supply the engine.

[0003] Currently, the fuel introduced into heat exchange devices such as fuel-liquid heat exchangers, fuel-hydraulic oil heat exchangers, and fuel-lubricating oil heat exchangers is basically maintained at a certain constant value or switches between a few constant values. The control mode is relatively simple, which cannot achieve flexible allocation of fuel heat sinks, cannot maximize the heat absorption capacity of fuel heat sinks, and results in significant heat sink waste. This makes it difficult to meet the needs of increasingly improved performance and growing cooling requirements of airborne equipment.

[0004] This application is made in view of the aforementioned technical deficiencies. Summary of the Invention

[0005] The purpose of this application is to provide an aircraft fuel heat sink cooling control system to overcome or mitigate at least one of the known technical defects.

[0006] The technical solution of this application is:

[0007] An aircraft fuel heat sink cooling control system includes: a variable frequency cooling pump, a fuel-cold liquid heat exchanger, a fuel-hydraulic oil heat exchanger, a fuel-lubricating oil heat exchanger, a first fuel flow calculator, a second fuel flow calculator, a third fuel flow calculator, and a controller.

[0008] The inlet of the variable frequency cooling pump is connected to the oil supply pipe via a pipeline, and the outlet is connected to the hot-side inlet of the fuel-cold liquid heat exchanger via a first control branch. The hot-side outlet of the fuel-cold liquid heat exchanger is connected to the hot-side inlet of the fuel-hydraulic oil heat exchanger via a pipeline. A first fuel temperature sensor is installed on this pipeline to measure the fuel temperature T8 at the hot-side outlet of the fuel-cold liquid heat exchanger. The cold-side inlet and outlet pipelines of the fuel-cold liquid heat exchanger are connected to the coolant. A first flow regulating valve is installed on the first control branch to regulate the fuel quantity of the first control branch, and a first fuel flow meter is installed to detect the fuel quantity Gt1 of the first control branch. A coolant temperature sensor is installed on the cold-side outlet pipeline of the fuel-cold liquid heat exchanger to detect the temperature T11 of the coolant after cooling.

[0009] The first fuel flow solver is connected to the first fuel temperature sensor and the coolant temperature sensor. Based on the hot-side outlet fuel temperature T8 of the fuel-cold liquid heat exchanger, the upper limit of fuel temperature TL, the temperature of the coolant after cooling T11, and the upper limit of coolant temperature TL11, it calculates the control flow rate G1 of the first control branch.

[0010] The outlet of the variable frequency cooling pump is connected to the hot-side inlet of the fuel-hydraulic oil heat exchanger via a second control branch. The hot-side outlet of the fuel-hydraulic oil heat exchanger is connected to the hot-side inlet of the fuel-lubricating oil heat exchanger via a pipeline. A second fuel temperature sensor is installed on this pipeline to measure the fuel temperature T9 at the hot-side outlet of the fuel-hydraulic oil heat exchanger. The cold-side inlet and outlet pipelines of the fuel-hydraulic oil heat exchanger are connected to hydraulic oil. A second flow regulating valve is installed on the second control branch to regulate the fuel quantity of the second control branch, and a second fuel flow meter is installed to detect the fuel quantity Gt2 of the second control branch. A hydraulic oil temperature sensor is installed on the cold-side outlet pipeline of the fuel-hydraulic oil heat exchanger to detect the temperature T12 of the cooled hydraulic oil.

[0011] The second fuel flow solver is connected to the second fuel temperature sensor and the hydraulic oil temperature sensor. Based on the hot-side outlet fuel temperature T9 of the fuel-hydraulic oil heat exchanger, the upper limit of fuel temperature TL, the temperature of the cooled hydraulic oil T12, and the upper limit of hydraulic oil temperature TL12, it calculates the control flow rate G2 of the second control branch.

[0012] The outlet of the variable frequency cooling pump is connected to the hot-side inlet of the fuel-oil heat exchanger via a third control branch. The hot-side outlet of the fuel-oil heat exchanger is connected to the hot-side inlet of the fuel supply pipe via a pipeline. A third fuel temperature sensor is installed on this pipeline to measure the fuel temperature T10 at the hot-side outlet of the fuel-oil heat exchanger. The cold-side inlet and outlet pipelines of the fuel-oil heat exchanger are connected to the lubricating oil. A third flow regulating valve is installed on the third control branch to regulate the fuel quantity in the third control branch, and a third fuel flow meter is installed to detect the fuel quantity Gt3 in the third control branch. A lubricating oil temperature sensor is installed on the cold-side outlet pipeline of the fuel-oil heat exchanger to detect the temperature T13 of the lubricating oil after cooling.

[0013] The third fuel flow solver is connected to the third fuel temperature sensor and the lubricating oil temperature sensor. Based on the hot-side outlet fuel temperature T10 of the fuel-lubricating oil heat exchanger, the upper limit of fuel temperature TL, the temperature of lubricating oil after cooling T13, and the upper limit of lubricating oil temperature TL13, it calculates the control flow rate G3 of the third control branch.

[0014] The controller connects to a variable frequency cooling pump, a first flow regulating valve, a second flow regulating valve, a third flow regulating valve, a first fuel flow meter, a second fuel flow meter, a third fuel flow meter, a first fuel flow calculator, a second fuel flow calculator, and a third fuel flow calculator. Based on the fuel quantity Gt1, the controlled flow rate G1, the fuel quantity Gt2, the controlled flow rate G2, the fuel quantity Gt3, and the controlled flow rate G3 of the first and third control branches, the controller calculates the control speed of the variable frequency cooling pump and the control opening degree of the first, second, and third flow regulating valves, thereby controlling the speed of the variable frequency cooling pump and the opening degree of the first, second, and third flow regulating valves.

[0015] Optionally, in the aforementioned aircraft fuel heat sink cooling control system, the first fuel flow solver calculates the control flow rate G1 of the first control branch based on the hot-side outlet fuel temperature T8 of the fuel-cold liquid heat exchanger, the upper limit of fuel temperature TL, the cooled liquid temperature T11, and the upper limit of coolant temperature TL11. Specifically:

[0016] TL-T8 and TL11-T11 are used as inputs to two fuel flow solvers based on the PID algorithm, and the larger of the two calculation results is taken as the control flow G1 of the first control branch.

[0017] Optionally, in the aforementioned aircraft fuel heat sink cooling control system, the second fuel flow solver calculates the control flow rate G2 of the second control branch based on the hot-side outlet fuel temperature T9 of the fuel-hydraulic oil heat exchanger, the upper limit of fuel temperature TL, the cooled hydraulic oil temperature T12, and the upper limit of hydraulic oil temperature TL12. Specifically:

[0018] TL-T9 and TL12-T12 are used as inputs to two fuel flow solvers based on the PID algorithm, and the larger of the two calculation results is taken as the control flow G2 of the second control branch.

[0019] Optionally, in the aforementioned aircraft fuel heat sink cooling control system, the third fuel flow solver calculates the control flow rate G3 of the third control branch based on the hot-side outlet fuel temperature T10 of the fuel-oil heat exchanger, the upper limit of fuel temperature TL, the temperature of the cooled oil T13, and the upper limit of the oil temperature TL13. Specifically, TL-T10 and TL13-T13 are used as inputs to two fuel flow solvers based on the PID algorithm, and the larger of the two calculation results is taken as the control flow rate G3 of the third control branch.

[0020] Optionally, in the aforementioned aircraft fuel heat sink cooling control system, the controller calculates the control speed of the variable frequency cooling pump and the control opening degrees of the first flow regulating valve, the second flow regulating valve, and the third flow regulating valve based on the fuel quantity Gt1, the control flow rate G1 of the first control branch, the fuel quantity Gt2, the control flow rate G2 of the second control branch, the fuel quantity Gt3, and the control flow rate G3 of the third control branch. Specifically:

[0021] Using [(G1+G2+G3)-(Gt1+Gt2+Gt3)] as an input to a fuel flow solver based on a PID algorithm, the control speed of the variable frequency cooling pump is calculated.

[0022] Using G1-Gt1 as an input to a fuel flow solver based on a PID algorithm, the control opening of the first flow regulating valve is calculated.

[0023] Using G2-Gt2 as an input to a fuel flow solver based on a PID algorithm, the control opening of the second flow regulating valve is calculated.

[0024] Using G3-Gt3 as an input to a fuel flow solver based on a PID algorithm, the control opening of the second flow regulating valve is calculated.

[0025] This application has at least the following beneficial technical effects:

[0026] In the aircraft fuel heat sink cooling control system disclosed in the above embodiments, considering the cooling requirements of coolant, hydraulic oil, and lubricating oil, the system is designed such that a portion of the fuel drawn from the fuel supply pipe by the variable frequency cooling pump flows through the fuel-cold liquid heat exchanger, fuel-hydraulic oil heat exchanger, and fuel-lubricating oil heat exchanger via a first control branch and returns to the fuel supply pipe; a portion flows through the fuel-hydraulic oil heat exchanger and fuel-lubricating oil heat exchanger via a second control branch and returns to the fuel supply pipe; and a portion flows through the fuel-lubricating oil heat exchanger via a third control branch and returns to the fuel supply pipe. This facilitates flexible and on-demand fuel allocation for efficient cooling of coolant, hydraulic oil, and lubricating oil. Furthermore, the system is designed based on the hot-side outlet fuel temperature T8 of the fuel-cold liquid heat exchanger, the upper limit of the fuel temperature TL, and the cooled coolant temperature T11. The upper limit of coolant temperature TL11, the hot-side outlet fuel temperature of the fuel-hydraulic oil heat exchanger T9, the cooled hydraulic oil temperature T12, the upper limit of hydraulic oil temperature TL12, the hot-side outlet fuel temperature of the fuel-lubricating oil heat exchanger T10, the cooled lubricating oil temperature T13, the upper limit of lubricating oil temperature TL13, and the fuel quantity Gt1 of the first control branch, the fuel quantity Gt2 of the second control branch, and the fuel quantity Gt3 of the third control branch are comprehensively calculated and controlled to adjust the speed of the variable frequency cooling pump and the opening of the first flow regulating valve, the second flow regulating valve, and the third flow regulating valve, thereby allocating the flow of the first control branch, the second control branch, and the third control branch to efficiently utilize the maximum heat absorption capacity of the fuel heat sink and avoid heat sink waste. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the aircraft fuel heat sink cooling control system provided in the embodiments of this application;

[0028] Figure 2 This is a schematic diagram illustrating how the aircraft fuel heat sink cooling control system provided in this application controls the rotational speed of the variable frequency cooling pump and the opening of the first flow regulating valve, the second flow regulating valve, and the third flow regulating valve.

[0029] in:

[0030] 1-Variable frequency cooling pump; 2-Fuel-cooled liquid heat exchanger; 3-Fuel-hydraulic oil heat exchanger; 4-Fuel-lubricating oil heat exchanger; 5-First flow regulating valve; 6-Second flow regulating valve; 7-Third flow regulating valve; 8-First fuel temperature sensor; 9-Second fuel temperature sensor; 10-Third fuel temperature sensor; 11-Coolant temperature sensor; 12-Hydraulic oil temperature sensor; 13-Lubricating oil temperature sensor; 14-First fuel flow meter; 15-Second fuel flow meter; 16-Third fuel flow meter; 17-First fuel flow calculator; 18-Second fuel flow calculator; 19-Third fuel flow calculator; 20-Controller.

[0031] To better illustrate this embodiment, some parts in the accompanying drawings may be omitted, enlarged, or reduced, and do not represent the actual product dimensions. Furthermore, the drawings are for illustrative purposes only and should not be construed as limiting this application. Detailed Implementation

[0032] To make the technical solution and advantages of this application clearer, the technical solution of this application will be described in a clearer and more complete manner below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only some embodiments of this application, and are only used to explain this application, not to limit this application. It should be noted that, for ease of description, only the parts related to this application are shown in the accompanying drawings, and other related parts can be referred to the general design.

[0033] Furthermore, unless otherwise defined, the technical or scientific terms used in this application description shall have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms indicating direction used in this application description are used only to indicate relative direction or positional relationship; when the absolute position of the described object changes, its relative positional relationship may also change accordingly. The word "comprising" as used in this application description indicates that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, but does not exclude other elements or objects.

[0034] Furthermore, it should be noted that, unless otherwise explicitly specified and limited, terms such as "installation" and "connection" used in the description of this application should be interpreted broadly. For example, a connection can be a fixed connection or a detachable connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand its specific meaning in this application according to the specific circumstances.

[0035] An aircraft fuel heat sink cooling control system, such as Figure 1 As shown, it includes a variable frequency cooling pump 1, a fuel-cold liquid heat exchanger 2, a fuel-hydraulic oil heat exchanger 3, a fuel-lubricating oil heat exchanger 4, a first fuel flow calculator 17, a second fuel flow calculator 18, a third fuel flow calculator 19, and a controller 20.

[0036] The inlet of the variable frequency cooling pump 1 is connected to the oil supply pipe through a pipeline, and the outlet is connected to the hot side inlet of the fuel-cold liquid heat exchanger 2 through the first control branch. The hot side outlet of the fuel-cold liquid heat exchanger 2 is connected to the hot side inlet of the fuel-hydraulic oil heat exchanger 3 through a pipeline. A first fuel temperature sensor 8 is installed on this pipeline to measure the fuel temperature T8 at the hot side outlet of the fuel-cold liquid heat exchanger 2. The cold side inlet and outlet pipelines of the fuel-cold liquid heat exchanger 2 are connected to the coolant. A first flow regulating valve 5 is installed on the first control branch to regulate the fuel quantity of the first control branch, and a first fuel flow meter 14 is installed to detect the fuel quantity Gt1 of the first control branch. A coolant temperature sensor 11 is installed on the cold side outlet pipeline of the fuel-cold liquid heat exchanger 2 to detect the temperature T11 of the coolant after cooling.

[0037] The first fuel flow solver 17 is connected to the first fuel temperature sensor 8 and the coolant temperature sensor 11. Based on the hot-side outlet fuel temperature T8 of the fuel-cold liquid heat exchanger 2, the upper limit of fuel temperature TL, the cooled coolant temperature T11, and the upper limit of coolant temperature TL11, it calculates the controlled flow rate G1 of the first control branch. Specifically, TL-T8 and TL11-T11 are used as inputs to two fuel flow solvers based on the PID algorithm, and the larger of the two calculation results is taken as the controlled flow rate G1 of the first control branch. Figure 2 As shown.

[0038] The outlet of the variable frequency cooling pump 1 is connected to the hot-side inlet of the fuel-hydraulic oil heat exchanger 3 through a second control branch. The hot-side outlet of the fuel-hydraulic oil heat exchanger 3 is connected to the hot-side inlet of the fuel-lubricating oil heat exchanger 4 through a pipeline. A second fuel temperature sensor 9 is installed on this pipeline to measure the fuel temperature T9 at the hot-side outlet of the fuel-hydraulic oil heat exchanger 3. The cold-side inlet and outlet pipelines of the fuel-hydraulic oil heat exchanger 3 are connected to hydraulic oil. A second flow regulating valve 6 is installed on the second control branch to regulate the fuel quantity of the second control branch, and a second fuel flow meter 15 is installed to detect the fuel quantity Gt2 of the second control branch. A hydraulic oil temperature sensor 12 is installed on the cold-side outlet pipeline of the fuel-hydraulic oil heat exchanger 3 to detect the temperature T12 of the cooled hydraulic oil.

[0039] The second fuel flow solver 18 is connected to the second fuel temperature sensor 9 and the hydraulic oil temperature sensor 12. Based on the hot-side outlet fuel temperature T9 of the fuel-hydraulic oil heat exchanger 3, the upper limit of fuel temperature TL, the cooled hydraulic oil temperature T12, and the upper limit of hydraulic oil temperature TL12, it calculates the controlled flow rate G2 of the second control branch. Specifically, TL-T9 and TL12-T12 are used as inputs to two fuel flow solvers based on the PID algorithm, and the larger of the two calculation results is taken as the controlled flow rate G2 of the second control branch. Figure 2 As shown.

[0040] The outlet of the variable frequency cooling pump 1 is connected to the hot side inlet of the fuel-oil heat exchanger 4 through a third control branch. The hot side outlet of the fuel-oil heat exchanger 4 is connected to the hot side inlet of the fuel supply pipe through a pipeline. A third fuel temperature sensor 10 is installed on this pipeline to measure the fuel temperature T10 at the hot side outlet of the fuel-oil heat exchanger 4. The cold side inlet and outlet pipelines of the fuel-oil heat exchanger 4 are connected to the lubricating oil. A third flow regulating valve 7 is installed on the third control branch to regulate the fuel quantity of the third control branch, and a third fuel flow meter 16 is installed to detect the fuel quantity Gt3 of the third control branch. A lubricating oil temperature sensor 13 is installed on the cold side outlet pipeline of the fuel-oil heat exchanger 4 to detect the temperature T13 of the lubricating oil after cooling.

[0041] The third fuel flow solver 19 is connected to the third fuel temperature sensor 10 and the lubricating oil temperature sensor 13. Based on the hot-side outlet fuel temperature T10 of the fuel-lubricating oil heat exchanger 4, the upper limit of fuel temperature TL, the cooled lubricating oil temperature T13, and the upper limit of lubricating oil temperature TL13, it calculates the control flow rate G3 of the third control branch. Specifically, TL-T10 and TL13-T13 are used as inputs to two fuel flow solvers based on the PID algorithm, and the larger of the two calculation results is taken as the control flow rate G3 of the third control branch. Figure 2 As shown.

[0042] The controller 20 is connected to the variable frequency cooling pump 1, the first flow regulating valve 5, the second flow regulating valve 6, the third flow regulating valve 7, the first fuel flow meter 14, the second fuel flow meter 15, the third fuel flow meter 16, the first fuel flow calculator 17, the second fuel flow calculator 18, and the third fuel flow calculator 19. Based on the fuel quantity Gt1, the controlled flow rate G1, the fuel quantity Gt2, the controlled flow rate G2, the fuel quantity Gt3, and the controlled flow rate G3 of the first controlled branch, it calculates the control speed of the variable frequency cooling pump 1 and the control opening degree of the first flow regulating valve 5, the second flow regulating valve 6, and the third flow regulating valve 7, and then controls the speed of the variable frequency cooling pump 1 and the opening degree of the first flow regulating valve 5, the second flow regulating valve 6, and the third flow regulating valve 7.

[0043] The controller 20 calculates the control speed of the variable frequency cooling pump 1 and the control opening degrees of the first flow regulating valve 5, the second flow regulating valve 6, and the third flow regulating valve 7 based on the fuel quantity Gt1 of the first control branch, the control flow rate G1 of the first control branch, the fuel quantity Gt2 of the second control branch, the control flow rate G2 of the second control branch, the fuel quantity Gt3 of the third control branch, and the control flow rate G3 of the third control branch. Specifically:

[0044] Using [(G1+G2+G3)-(Gt1+Gt2+Gt3)] as an input to a fuel flow solver based on a PID algorithm, the control speed of the variable frequency cooling pump 1 is calculated.

[0045] Using G1-Gt1 as an input to a fuel flow solver based on a PID algorithm, the control opening of the first flow regulating valve 5 is calculated.

[0046] Using G2-Gt2 as an input to a fuel flow solver based on a PID algorithm, the control opening of the second flow regulating valve 6 is calculated.

[0047] Using G3-Gt3 as an input to a fuel flow solver based on a PID algorithm, the control opening of the second flow regulating valve 6 is calculated.

[0048] In the aircraft fuel heat sink cooling control system disclosed in the above embodiments, considering the cooling requirements of coolant, hydraulic oil, and lubricating oil, the system is designed such that a portion of the fuel drawn from the fuel supply pipe by the variable frequency cooling pump 1 flows through the fuel-cold liquid heat exchanger 2, fuel-hydraulic oil heat exchanger 3, and fuel-lubricating oil heat exchanger 4 via a first control branch and returns to the fuel supply pipe; a portion flows through the fuel-hydraulic oil heat exchanger 3 and fuel-lubricating oil heat exchanger 4 via a second control branch and returns to the fuel supply pipe; and a portion flows through the fuel-lubricating oil heat exchanger 4 via a third control branch and returns to the fuel supply pipe. This facilitates flexible and on-demand fuel allocation for efficient cooling of coolant, hydraulic oil, and lubricating oil. Furthermore, the system is designed based on the hot-side outlet fuel temperature T8 of the fuel-cold liquid heat exchanger 2, the upper limit of the fuel temperature TL, and the cooled coolant temperature T11. The system comprehensively calculates and controls the speed of the variable frequency cooling pump 1 and the opening degrees of the first flow regulating valve 5, the second flow regulating valve 6, and the third flow regulating valve 7, as well as the upper limit of the coolant temperature TL11, the hot-side outlet fuel temperature T9 of the fuel-hydraulic oil heat exchanger 3, the cooled hydraulic oil temperature T12, the upper limit of the hydraulic oil temperature TL12, the hot-side outlet fuel temperature T10 of the fuel-lubricating oil heat exchanger 4, the cooled lubricating oil temperature T13, the upper limit of the lubricating oil temperature TL13, the fuel quantity Gt1 of the first control branch, the fuel quantity Gt2 of the second control branch, and the fuel quantity Gt3 of the third control branch. This, along with the flow rates of the first control branch, the second control branch, and the third control branch, ensures efficient utilization of the maximum heat absorption capacity of the fuel heat sink and avoids heat sink waste.

[0049] Furthermore, those skilled in the art should recognize that the first fuel flow solver 17, the second fuel flow solver 18, the third fuel flow solver 19, the controller 20, and their PID algorithm fuel flow solver in the aircraft fuel heat sink cooling control system disclosed in the embodiments of this application can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, they are generally described in terms of function in this application. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can choose different methods to implement the described functions for each specific application and its actual constraints, but such implementation should not be considered beyond the scope of this application.

[0050] The technical solution of this application has been described in conjunction with the preferred embodiments shown in the accompanying drawings. Those skilled in the art should understand that the scope of protection of this application is obviously not limited to these specific embodiments. Without departing from the principles of this application, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of this application.

Claims

1. An aircraft fuel heat sink cooling control system, characterized in that, include: Variable frequency cooling pump (1), fuel-cold liquid heat exchanger (2), fuel-hydraulic oil heat exchanger (3), fuel-lubricating oil heat exchanger (4), first fuel flow calculator (17), second fuel flow calculator (18), third fuel flow calculator (19), controller (20). The inlet of the variable frequency cooling pump (1) is connected to the oil supply pipe through a pipeline, and the outlet is connected to the hot side inlet of the fuel-cold liquid heat exchanger (2) through the first control branch. The hot side outlet of the fuel-cold liquid heat exchanger (2) is connected to the hot side inlet of the fuel-hydraulic oil heat exchanger (3) through a pipeline. A first fuel temperature sensor (8) is installed on this pipeline to measure the fuel temperature T8 at the hot side outlet of the fuel-cold liquid heat exchanger (2). The cold side inlet and outlet pipelines of the fuel-cold liquid heat exchanger (2) are connected to the coolant. A first flow regulating valve (5) is installed on the first control branch to regulate the fuel quantity of the first control branch, and a first fuel flow meter (14) is installed to detect the fuel quantity Gt1 of the first control branch. A coolant temperature sensor (11) is installed on the cold side outlet pipeline of the fuel-cold liquid heat exchanger (2) to detect the temperature T11 of the coolant after cooling. The first fuel flow solver (17) is connected to the first fuel temperature sensor (8) and the coolant temperature sensor (11). Based on the hot-side outlet fuel temperature T8, the upper limit of fuel temperature TL, the temperature of the coolant after cooling T11, and the upper limit of coolant temperature TL11 of the fuel-cold liquid heat exchanger (2), it calculates the control flow rate G1 of the first control branch. The outlet of the variable frequency cooling pump (1) is connected to the hot side inlet of the fuel-hydraulic oil heat exchanger (3) through the second control branch. The hot side outlet of the fuel-hydraulic oil heat exchanger (3) is connected to the hot side inlet of the fuel-lubricating oil heat exchanger (4) through a pipeline. A second fuel temperature sensor (9) is installed on the pipeline to measure the fuel temperature T9 at the hot side outlet of the fuel-hydraulic oil heat exchanger (3). The cold side inlet and outlet pipelines of the fuel-hydraulic oil heat exchanger (3) are connected to hydraulic oil. A second flow regulating valve (6) is installed on the second control branch to regulate the fuel oil quantity of the second control branch, and a second fuel flow meter (15) is installed to detect the fuel oil quantity Gt2 of the second control branch. A hydraulic oil temperature sensor (12) is installed on the cold side outlet pipeline of the fuel-hydraulic oil heat exchanger (3) to detect the temperature T12 of the hydraulic oil after cooling. The second fuel flow solver (18) is connected to the second fuel temperature sensor (9) and the hydraulic oil temperature sensor (12). Based on the hot-side outlet fuel temperature T9, the upper limit of fuel temperature TL, the temperature of the hydraulic oil after cooling T12, and the upper limit of hydraulic oil temperature TL12 of the fuel-hydraulic oil heat exchanger (3), it calculates the control flow rate G2 of the second control branch. The outlet of the variable frequency cooling pump (1) is connected to the hot side inlet of the fuel-oil heat exchanger (4) through the third control branch. The hot side outlet of the fuel-oil heat exchanger (4) is connected to the hot side inlet of the oil supply pipe through a pipeline. A third fuel temperature sensor (10) is installed on the pipeline to measure the fuel temperature T10 at the hot side outlet of the fuel-oil heat exchanger (4). The cold side inlet and outlet pipelines of the fuel-oil heat exchanger (4) are connected to the lubricating oil. A third flow regulating valve (7) is installed on the third control branch to regulate the fuel quantity of the third control branch, and a third fuel flow meter (16) is installed to detect the fuel quantity Gt3 of the third control branch. A lubricating oil temperature sensor (13) is installed on the cold side outlet pipeline of the fuel-oil heat exchanger (4) to detect the temperature T13 of the lubricating oil after cooling. The third fuel flow solver (19) is connected to the third fuel temperature sensor (10) and the lubricating oil temperature sensor (13). Based on the hot-side outlet fuel temperature T10, the upper limit of fuel temperature TL, the temperature of lubricating oil after cooling T13, and the upper limit of lubricating oil temperature TL13 of the fuel-lubricating oil heat exchanger (4), it calculates the control flow G3 of the third control branch. The controller (20) is connected to the variable frequency cooling pump (1), the first flow regulating valve (5), the second flow regulating valve (6), the third flow regulating valve (7), the first fuel flow meter (14), the second fuel flow meter (15), the third fuel flow meter (16), the first fuel flow calculator (17), the second fuel flow calculator (18), and the third fuel flow calculator (19). Based on the fuel quantity Gt1 of the first control branch, the control flow G1 of the first control branch, the fuel quantity Gt2 of the second control branch, the control flow G2 of the second control branch, the fuel quantity Gt3 of the third control branch, and the control flow G3 of the third control branch, the controller calculates the control speed of the variable frequency cooling pump (1) and the control opening of the first flow regulating valve (5), the second flow regulating valve (6), and the third flow regulating valve (7), and then controls the speed of the variable frequency cooling pump (1) and the opening of the first flow regulating valve (5), the second flow regulating valve (6), and the third flow regulating valve (7).

2. The aircraft fuel heat sink cooling control system according to claim 1, characterized in that, The first fuel flow solver (17) calculates the control flow rate G1 of the first control branch based on the hot-side outlet fuel temperature T8, the upper limit of fuel temperature TL, the temperature of the coolant after cooling T11, and the upper limit of coolant temperature TL11 of the fuel-cold liquid heat exchanger (2). Specifically: TL-T8 and TL11-T11 are used as inputs to two fuel flow solvers based on the PID algorithm, and the larger of the two calculation results is taken as the control flow G1 of the first control branch.

3. The aircraft fuel heat sink cooling control system according to claim 2, characterized in that, The second fuel flow solver (18) calculates the control flow rate G2 of the second control branch based on the hot-side outlet fuel temperature T9, the upper limit of fuel temperature TL, the temperature of the cooled hydraulic oil T12, and the upper limit of hydraulic oil temperature TL12 of the fuel-hydraulic oil heat exchanger (3). Specifically: TL-T9 and TL12-T12 are used as inputs to two fuel flow solvers based on the PID algorithm, and the larger of the two calculation results is taken as the control flow G2 of the second control branch.

4. The aircraft fuel heat sink cooling control system according to claim 3, characterized in that, The third fuel flow solver (19) calculates the control flow rate G3 of the third control branch based on the hot-side outlet fuel temperature T10, the upper limit of fuel temperature TL, the temperature of lubricating oil after cooling T13, and the upper limit of lubricating oil temperature TL13 of the fuel-lubricating oil heat exchanger (4). Specifically, TL-T10 and TL13-T13 are used as inputs to two fuel flow solvers based on the PID algorithm, and the larger value of the two calculation results is taken as the control flow rate G3 of the third control branch.

5. The aircraft fuel heat sink cooling control system according to claim 4, characterized in that, The controller (20) calculates the control speed of the variable frequency cooling pump (1) and the control opening of the first flow regulating valve (5), the second flow regulating valve (6), and the third flow regulating valve (7) based on the fuel quantity Gt1 of the first control branch, the control flow rate G1 of the first control branch, the fuel quantity Gt2 of the second control branch, the control flow rate G2 of the second control branch, the fuel quantity Gt3 of the third control branch, and the control flow rate G3 of the third control branch. Specifically: Using [(G1+G2+G3)-(Gt1+Gt2+Gt3)] as an input to a fuel flow solver based on a PID algorithm, the control speed of the variable frequency cooling pump (1) is calculated; Using G1-Gt1 as an input to a fuel flow solver based on a PID algorithm, the control opening of the first flow regulating valve (5) is calculated. Using G2-Gt2 as an input to a fuel flow solver based on a PID algorithm, the control opening of the second flow regulating valve (6) is calculated. Using G3-Gt3 as an input to a fuel flow solver based on a PID algorithm, the control opening of the third flow regulating valve (7) is calculated.

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