Intelligent casing pipe system and method for aircraft high-temperature air entraining pipeline

Abstract

The invention discloses an intelligent sleeve system for an aircraft high-temperature air entraining pipeline, which comprises a first fiber bragg grating temperature sensor, a second fiber bragg grating temperature sensor, a third fiber bragg grating temperature sensor, a fourth fiber bragg grating temperature sensor, a fourth fiber bragg grating temperature sensor and a fifth fiber bragg grating temperature sensor, the second fiber bragg grating temperature sensor monitors the temperature of the corresponding position of the joint of the air-entraining guide pipe of the aircraft through each grating to obtain distributed temperature data of the joint of the air-entraining guide pipe of the aircraft; the air-entraining conduit temperature field construction module constructs an air-entraining conduit temperature field model by adopting an interpolation-based temperature field reduction algorithm according to the distributed temperature data of the airplane air-entraining conduit body and the distributed temperature data at the joint, and obtains the temperature data of each point of the airplane air-entraining conduit by utilizing the air-entraining conduit temperature field model; and the air-entraining leakage condition is judged by utilizing the temperature data of each point of the air-entraining guide pipe of the aircraft. According to the invention, rapid monitoring and positioning of leakage of the air-entraining pipeline of the airplane are realized, and the reliability of leakage alarm is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of aircraft high-temperature pipelines, and in particular to an intelligent casing system and method for aircraft high-temperature bleed air pipelines. Background Art

[0002] The aircraft air duct system is an important part of the aircraft air management system. The bleed air duct may leak during the operation of the aircraft. If a high-temperature bleed air leak occurs due to a rupture or damage to the duct, it may cause the rudder fan bracket, pressure floor, pressure floor beam, fuel ventilation box or fuel line to be exposed to high temperature. This may cause loss of rudder control and reduce the structural integrity of the main structure or fuel ignition. It can be seen that the high-pressure pipeline leak must be monitored to protect the aircraft systems, equipment and structures around the leaking pipeline.

[0003] The aircraft bleed air duct is divided into an inner tube and an outer tube, with a layer of air between the inner and outer tubes acting as an insulator. High-temperature and high-pressure aircraft bleed air is transmitted in the inner tube. In addition to protecting and insulating, the outer tube has a guide hole at regular intervals. When the bleed air leaks, the leaked hot air flows out from the guide hole on the outer tube, heating the surrounding air to the alarm threshold and then being detected by the temperature sensing component arranged above the guide hole, thereby triggering a leakage alarm. However, investigations have shown that when a pipeline leaks, the aircraft bleed air leakage detection system may miss an alarm. On the one hand, the gas flowing out of the guide hole may not be able to heat the temperature sensing component above the guide hole to the alarm threshold. On the other hand, since the temperature sensing component is currently only installed above the bleed air duct, it may not be possible to monitor bleed air leaks at the bottom of the bleed air duct or in other directions. For example, the bleed air at the bleed air duct joint may leak in any direction.

[0004] As civil aviation standards continue to increase their requirements for aircraft safety, how to reduce the occurrence of missed alarms in aircraft bleed air duct leakage monitoring, achieve rapid monitoring and positioning of aircraft bleed air duct leakage, and improve the reliability of leakage alarms have become key technical problems that need to be solved urgently. Summary of the invention

[0005] The purpose of the present invention is to provide an intelligent casing system and method for aircraft high-temperature bleed air pipelines. The present invention reduces the probability of missed alarms and false alarms in aircraft bleed air pipeline leakage monitoring, realizes rapid monitoring and positioning of aircraft bleed air pipeline leakage, and improves the reliability of leakage alarms.

[0006] To achieve this purpose, the intelligent casing system designed by the present invention for aircraft high-temperature bleed air pipeline comprises a bleed air duct temperature field building module, an insulating casing sleeved outside the aircraft bleed air duct, a first fiber grating temperature sensor attached to the inner wall of the insulating casing, a temperature monitoring ring sleeved at the aircraft bleed air duct joint, and a second fiber grating temperature sensor attached to the inner wall of the temperature monitoring ring, wherein the first fiber grating temperature sensor is connected to the second fiber grating temperature sensor;

[0007] The first fiber grating temperature sensor monitors the temperature at the corresponding position of the aircraft bleed air duct body through each grating, thereby obtaining the distributed temperature data of the aircraft bleed air duct body, and the second fiber grating temperature sensor monitors the temperature at the corresponding position of the aircraft bleed air duct joint through each grating, thereby obtaining the distributed temperature data of the aircraft bleed air duct joint;

[0008] The bleed air duct temperature field construction module is used to construct a bleed air duct temperature field model according to the distributed temperature data of the aircraft bleed air duct body and the distributed temperature data at the aircraft bleed air duct joint using an interpolation-based temperature field restoration algorithm, and use the bleed air duct temperature field model to obtain the temperature data of each point in the aircraft bleed air duct, and use the temperature data of each point in the aircraft bleed air duct to judge the bleed air leakage situation.

[0009] Preferably, the outer wall of the insulating sleeve is fixed to the fuselage positioning plate outside the aircraft bleed air duct, so that the insulating sleeve is suspended outside the aircraft bleed air duct, an air insulation layer is provided between the insulating sleeve and the aircraft bleed air duct, the joint of the insulating sleeve is located at the periphery of the joint of the aircraft bleed air duct, and the temperature monitoring ring is coaxially fixed at the joint of the insulating sleeve, and an air insulation layer is provided between the temperature monitoring ring and the aircraft bleed air duct.

[0010] Preferably, the insulating sleeve includes hinged rings at both ends, and a rectangular insulating layer arranged between the hinged rings at both ends. After the hinged rings at both ends are clamped by a first buckle, the rectangular insulating layer is rolled into a sleeve shape, and the first fiber grating temperature sensor is reciprocally attached to the inner wall of the rectangular insulating layer in a triangular shape, so that the distributed temperature data of the aircraft air bleed duct body can be obtained after the rectangular insulating layer is rolled into a sleeve shape.

[0011] Preferably, optical fiber connectors are provided at both ends of the temperature monitoring ring, and the first optical fiber Bragg grating temperature sensor and the second optical fiber Bragg grating temperature sensor are connected via the optical fiber connectors;

[0012] The temperature monitoring ring is an articulated monitoring ring. The second fiber grating temperature sensor is reciprocatingly attached to the inner wall of the articulated monitoring ring. The temperature monitoring ring is locked by a second buckle. The second fiber grating temperature sensor monitors the temperature of the corresponding position of the aircraft bleed air duct joint through each grating, thereby obtaining distributed temperature data at the aircraft bleed air duct joint.

[0013] A method for monitoring bleed air leakage in a high-temperature bleed air pipeline of an aircraft based on the above system comprises the following steps:

[0014] The first fiber grating temperature sensor monitors the temperature at the corresponding position of the aircraft bleed air duct body through each grating, thereby obtaining the distributed temperature data of the aircraft bleed air duct body, and the second fiber grating temperature sensor monitors the temperature at the corresponding position of the aircraft bleed air duct joint through each grating, thereby obtaining the distributed temperature data of the aircraft bleed air duct joint;

[0015] According to the distributed temperature data of the aircraft bleed air duct body and the distributed temperature data at the aircraft bleed air duct joint, a bleed air duct temperature field model is constructed by using an interpolation-based temperature field restoration algorithm. The bleed air duct temperature field model is used to obtain the temperature data of each point in the aircraft bleed air duct, and the bleed air leakage situation is judged by using the temperature data of each point in the aircraft bleed air duct.

[0016] A computer program product comprises a computer program, wherein the computer program implements the steps of the above method when executed by a processor.

[0017] A computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the above method are implemented.

[0018] Beneficial effects of the present invention:

[0019] The present invention installs a fiber grating temperature sensor inside the aircraft high-temperature bleed air duct to conduct comprehensive and highly sensitive leakage monitoring of the aircraft bleed air system, so as to timely discover tiny leakage points and prevent safety hazards and performance degradation caused by leakage; the design of the insulating sleeve to separate the air insulation layer from the external environment effectively isolates the influence of the bleed air duct on the external environment and prevents the high-temperature bleed air duct from heating the surrounding air; the real-time monitoring and positioning of the bleed air duct temperature and leakage are realized in an intelligent manner, which reduces manual intervention and improves the timeliness and accuracy of monitoring; the leakage points are discovered and repaired in time, the reliability of the leakage alarm is improved, and greater losses and maintenance costs caused by leakage are avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural schematic diagram of the present invention;

[0021] Figure 2 It is a schematic diagram of the structure of the thermal insulation sleeve of the present invention;

[0022] Figure 3 It is a schematic diagram of the three-dimensional structure of the thermal insulation sleeve of the present invention;

[0023] Figure 4 This is the development diagram of the inner wall of the thermal insulation casing;

[0024] Figure 5 It is the side view of the temperature monitoring ring;

[0025] Figure 6 This is the internal structure diagram of the temperature monitoring loop;

[0026] Figure 7 This is the connection diagram between the temperature monitoring ring and the insulation sleeve;

[0027] Figure 8 is a flow chart of the present invention;

[0028] Fig. 9 This is a schematic diagram of the current aircraft bleed air duct structure;

[0029] Fig.10 It is the temperature field diagram of the insulation casing;

[0030] Among them, 1-insulating sleeve, 1.1-hinge ring, 1.2-rectangular insulation layer, 1.3-first buckle, 2-aircraft air bleed duct, 3-first fiber grating temperature sensor, 4-temperature monitoring ring, 4.1-second buckle, 5-second fiber grating temperature sensor, 6-air insulation layer, 7-optical fiber connector. DETAILED DESCRIPTION

[0031] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments:

[0032] Example 1

[0033] An intelligent casing system for aircraft high temperature bleed air pipelines, such as Figure 1 , 2 , 3, 4, 5, 6, and 7, it includes a bleed air duct temperature field construction module, an insulating sleeve 1 sleeved outside the aircraft bleed air duct 2, a first fiber Bragg grating temperature sensor 3 attached to the inner wall of the insulating sleeve 1, a temperature monitoring ring 4 sleeved at the joint of the aircraft bleed air duct 2, and a second fiber Bragg grating temperature sensor 5 attached to the inner wall of the temperature monitoring ring 4, and the first fiber Bragg grating temperature sensor 3 is connected to the second fiber Bragg grating temperature sensor 5;

[0034] The first fiber grating temperature sensor 3 monitors the temperature at the corresponding position of the aircraft bleed air duct 2 through each grating, thereby obtaining the distributed temperature data of the aircraft bleed air duct 2, and the second fiber grating temperature sensor 5 monitors the temperature at the corresponding position of the joint of the aircraft bleed air duct 2 through each grating, thereby obtaining the distributed temperature data of the joint of the aircraft bleed air duct 2;

[0035] The bleed air duct temperature field construction module is used to construct a bleed air duct temperature field model according to the distributed temperature data of the aircraft bleed air duct 2 body and the distributed temperature data at the joint of the aircraft bleed air duct 2 using an interpolation-based temperature field restoration algorithm, and use the bleed air duct temperature field model to obtain the temperature data of each point of the aircraft bleed air duct 2, and use the temperature data of each point of the aircraft bleed air duct 2 to judge the bleed air leakage. This design uses an interpolation-based temperature field restoration algorithm, which can use limited distributed temperature data points to obtain the distribution of the entire duct temperature field through algorithm calculation, thereby improving the accuracy and comprehensiveness of temperature monitoring.

[0036] In the above technical scheme, the outer wall of the insulating sleeve 1 is fixed on the fuselage positioning plate outside the aircraft bleed air duct 2, so that the insulating sleeve 1 is suspended outside the aircraft bleed air duct 2, and an air insulation layer 6 is provided between the insulating sleeve 1 and the aircraft bleed air duct 2 (the air insulation layer 6 is provided because the temperature of the aircraft bleed air duct 2 is too high, and it is convenient to isolate it from the external environment, so as not to affect the aircraft cabin environment, and play a protective and heat-insulating role), the joint of the insulating sleeve 1 is located at the periphery of the joint of the aircraft bleed air duct 2, and the temperature monitoring ring 4 is coaxially fixed at the joint of the insulating sleeve 1, and an air insulation layer 6 is provided between the temperature monitoring ring 4 and the aircraft bleed air duct 2. The above design forms an effective heat-insulating barrier through the air insulation layer 6 provided between the insulating sleeve 1 and the aircraft bleed air duct 2, which can isolate the high temperature of the bleed air duct and prevent it from being directly transmitted to the fuselage or the interior of the cabin, thereby protecting the cabin environment from being affected by high temperature.

[0037] In the above technical scheme, the insulating sleeve 1 includes hinged rings 1.1 at both ends, and a rectangular insulating layer 1.2 arranged between the hinged rings at both ends. After the hinged rings 1.1 at both ends are clamped by the first buckle 1.3, the rectangular insulating layer 1.2 is rolled into a sleeve shape, and the first fiber grating temperature sensor 3 is reciprocally attached to the inner wall of the rectangular insulating layer 1.2 in a triangular shape, so that the distributed temperature data of the aircraft bleed air duct 2 body can be obtained after the rectangular insulating layer 1.2 is rolled into a sleeve shape (the first fiber grating temperature sensor 3 is attached to the inner wall of the insulating sleeve 1 and fixed by a mounting bracket; the inner wall of the insulating sleeve 1 is a space closed surface with a diameter of d, and the inner wall of the insulating sleeve is unfolded, and the unfolded two-dimensional figure is a rectangle with a length of L and a width of πd, and D is the effective distance for bleed air leakage identification; when When the number of winding turns is greater than or equal to When the first fiber grating temperature sensor is in the circle, it can realize the comprehensive monitoring of the bleed air leakage of the aircraft bleed air duct 2). The above design is used to facilitate the opening and closing, disassembly and assembly of the insulation sleeve 1.

[0038] In the above technical solution, optical fiber connectors are provided at both ends of the temperature monitoring ring 4, and the first optical fiber Bragg grating temperature sensor 3 and the second optical fiber Bragg grating temperature sensor 5 are connected via an optical fiber connector 7;

[0039] The temperature monitoring ring 4 is an articulated monitoring ring, and the second fiber grating temperature sensor 5 is reciprocatingly attached to the inner wall of the articulated monitoring ring. The temperature monitoring ring 4 is clamped by the second buckle 4.1, and the second fiber grating temperature sensor 5 monitors the temperature of the corresponding position of the joint of the aircraft air bleed duct 2 through each grating, thereby obtaining the distributed temperature data of the joint of the aircraft air bleed duct 2. The above design makes the installation and maintenance process of the temperature monitoring ring simpler and faster through the use of the articulated design and the fiber optic connector. When the sensor needs to be replaced or repaired, it only needs to be plugged in and out through the fiber optic connector without disassembling the entire monitoring ring.

[0040] In the above technical solution, the specific method of the bleed air duct temperature field construction module to construct the bleed air duct temperature field model using the interpolation-based temperature field restoration algorithm according to the distributed temperature data of the aircraft bleed air duct 2 pipe body and the distributed temperature data at the aircraft bleed air duct 2 joint is:

[0041] Assume that the temperature of any point on the inner wall of the insulating sleeve 1 and the temperature monitoring ring 4 is T(x, y, z), (x, y, z)∈A, A is the set of all points on the inner wall of the insulating sleeve 1 and the temperature monitoring ring 4, and the total number of gratings of the first fiber grating temperature sensor 3 and the second fiber grating temperature sensor 5 is n. At time t, the temperature data T(x) of n points on the inner wall of the insulating sleeve 1 and the temperature monitoring ring 4 are obtained. i ,y i , z i ), (x i ,y i , z i )∈A, i=1, 2, ..., n, use these n points as sample functions and define the interpolation function

[0042]

[0043] Where r = || xx i ,yy i ,zz i || represents the midpoint (x, y, z) between the insulation sleeve 1 and the temperature monitoring ring 4 and the point (x i ,y i , z i )’s Euclidean distance, w i Weight coefficient (w i The weight coefficient is calculated by bringing the temperature value of the point obtained by the sensor into the difference model), φ is the radial basis function, Where α is the shape parameter of the radial basis function, φ(r) is the basis function, and e is a natural constant;

[0044] function Satisfy the interpolation conditions:

[0045]

[0046] Substituting n sample points into the above formula, we have:

[0047]

[0048] make

[0049] The above formula can be simplified to obtain the airway duct temperature field model:

[0050] T = wv;

[0051] The above design infers the temperature of the unknown point through the temperature of the detection point. From point to surface, the interpolation algorithm can use the temperature information of a limited number of known measuring points to infer the temperature values ​​of other unknown points in the temperature field through mathematical methods. This method does not rely on complete temperature field data and only requires a small number of known points. The interpolation algorithm is based on the spatial position relationship and believes that the closer the points are in spatial position, the more similar their temperature values ​​are. It is especially suitable for areas where the temperature field distribution is relatively uniform or the changes are relatively gentle.

[0052] In the above technical solution, the linear combination coefficient w is obtained by solving the linear equations, and w is substituted into The interpolation model obtained is the temperature field model of the airway duct. The above design is used to obtain the temperature field model of the airway duct.

[0053] In the above technical scheme, the area where the temperature gradient in the bleed air duct temperature field model is greater than the threshold is the bleed air leakage area (under normal circumstances, the temperature gradient is 2 orders of magnitude smaller than the leakage), and the temperature at the point where the temperature gradient is greater than the threshold is taken as the isotherm, and its isotherm contour is used to characterize the size and shape of the bleed air leakage. The above design realizes the precise positioning and quantitative characterization of the bleed air leakage area through temperature gradient analysis and isotherm contour analysis, which provides strong support for subsequent maintenance work and helps to improve the overall performance and safety of the aircraft bleed air duct system.

[0054] Example 2

[0055] An intelligent casing method for aircraft high temperature bleed air pipelines, such as Figure 8 shown.

[0056] The specific method of the intelligent sleeve for the high temperature bleed air pipeline of the aircraft includes the following steps:

[0057] The first fiber grating temperature sensor 3 monitors the temperature at the corresponding position of the aircraft bleed air duct 2 through each grating, thereby obtaining the distributed temperature data of the aircraft bleed air duct 2, and the second fiber grating temperature sensor 5 monitors the temperature at the corresponding position of the joint of the aircraft bleed air duct 2 through each grating, thereby obtaining the distributed temperature data of the joint of the aircraft bleed air duct 2;

[0058] According to the distributed temperature data of the aircraft bleed air duct 2 body and the distributed temperature data at the joint of the aircraft bleed air duct 2, a bleed air duct temperature field model is constructed by using an interpolation-based temperature field restoration algorithm. The bleed air duct temperature field model is used to obtain the temperature data of each point in the aircraft bleed air duct 2, and the bleed air leakage situation is judged by using the temperature data of each point in the aircraft bleed air duct 2.

[0059] Example 3

[0060] An intelligent casing system for aircraft high temperature bleed air pipelines, such as Figure 2 , 3 , 9, it includes:

[0061] Fig. 9 It is a schematic diagram of the current aircraft bleed air duct structure, which is mainly composed of the bleed air duct, a solid insulation layer and a guide hole; the function of the solid insulation layer is to separate the high-temperature bleed air duct from the surrounding cabin environment, and the insulation layer is provided with a guide hole. When a leak occurs in the pipeline, the leaked gas flows out from the guide hole and is finally sensed by the eutectic salt sensor. Figure 2 , Figure 3 , is a schematic diagram of the structure of the insulating sleeve 1 designed based on the characteristics of the optical fiber sensor of the present invention: the insulating sleeve 1 has no guide holes, which simplifies the original duct structure; the insulating sleeve 1 uses air as the insulating layer material, and uses thin-walled aviation metal as the outer wall to separate the air insulating layer from the external environment, which further simplifies the duct structure and reduces the cost; the insulating sleeve 1 can be opened and closed up and down, and the first optical fiber grating temperature sensor 3 is reciprocally attached in a triangular shape by installing a bracket on the inner wall of the insulating sleeve 1, and the insulating sleeve 1 can be directly sleeved on the bleed air duct 2, which greatly reduces the cabin space occupied by the bleed air duct 2 and the leakage monitoring device.

[0062] Example 4

[0063] An intelligent casing system for aircraft high temperature bleed air pipelines, such as Fig.10 As shown, it includes:

[0064] The interpolation model is used to realize the real-time restoration of the temperature field of the insulation sleeve. The temperature field of the insulation sleeve 10s after the catheter leaks is as follows: Fig.10As shown, the area where the temperature gradient in the air duct temperature field model is greater than the threshold is the air duct leakage area, and the area where the isotherm contour is greater than the quantization error is used to characterize the size and shape of the air duct leakage. It can realize leakage monitoring of the air duct without leakage points and can realize accurate positioning of the leakage. At the same time, this method does not need to wait for the temperature to be heated to the threshold temperature before issuing an alarm, which greatly shortens the alarm response time.

[0065] Example 5

[0066] A computer program product includes a computer program, characterized in that when the computer program is executed by a processor, the steps of the method described in Example 2 are implemented.

[0067] Example 6

[0068] A computer-readable storage medium stores a computer program, wherein the computer program implements the steps of the method described in Example 2 when executed by a processor.

[0069] The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field.

Claims

1. An intelligent casing system for aircraft high-temperature bleed air pipelines, characterized in that: It comprises a bleed air duct temperature field building module, a heat-insulating sleeve (1) sleeved outside the aircraft bleed air duct (2), a first fiber grating temperature sensor (3) attached to the inner wall of the heat-insulating sleeve (1), a temperature monitoring ring (4) sleeved at the joint of the aircraft bleed air duct (2), and a second fiber grating temperature sensor (5) attached to the inner wall of the temperature monitoring ring (4); the first fiber grating temperature sensor (3) is connected to the second fiber grating temperature sensor (5); The first fiber grating temperature sensor (3) monitors the temperature at corresponding positions of the aircraft bleed air duct (2) through each grating, thereby obtaining distributed temperature data of the aircraft bleed air duct (2) body, and the second fiber grating temperature sensor (5) monitors the temperature at corresponding positions of the aircraft bleed air duct (2) joint through each grating, thereby obtaining distributed temperature data of the aircraft bleed air duct (2) joint; The bleed air duct temperature field construction module is used to construct a bleed air duct temperature field model based on the distributed temperature data of the aircraft bleed air duct (2) pipe body and the distributed temperature data at the joint of the aircraft bleed air duct (2) using an interpolation-based temperature field restoration algorithm, obtain the temperature data of each point of the aircraft bleed air duct (2) using the bleed air duct temperature field model, and judge the bleed air leakage situation using the temperature data of each point of the aircraft bleed air duct (2).

2. The intelligent casing system for aircraft high temperature bleed air pipeline according to claim 1, characterized in that: The outer wall of the thermal insulation sleeve (1) is fixed on a fuselage positioning plate outside the aircraft bleed air duct (2), so that the thermal insulation sleeve (1) is suspended outside the aircraft bleed air duct (2), an air insulation layer (6) is provided between the thermal insulation sleeve (1) and the aircraft bleed air duct (2), a joint of the thermal insulation sleeve (1) is located outside the joint of the aircraft bleed air duct (2), a temperature monitoring ring (4) is coaxially fixed at the joint of the thermal insulation sleeve (1), and an air insulation layer (6) is provided between the temperature monitoring ring (4) and the aircraft bleed air duct (2).

3. The intelligent casing system for aircraft high temperature bleed air pipeline according to claim 1, characterized in that: The thermal insulation sleeve (1) comprises hinged rings (1.1) at two ends and a rectangular thermal insulation layer (1.2) arranged between the hinged rings at the two ends; after the hinged rings (1.1) at the two ends are clamped by a first buckle (1.3), the rectangular thermal insulation layer (1.2) is rolled into a sleeve shape; the first fiber optic grating temperature sensor (3) is reciprocally attached to the inner wall of the rectangular thermal insulation layer (1.2) in a triangular shape, so that after the rectangular thermal insulation layer (1.2) is rolled into a sleeve shape, distributed temperature data of the pipe body of the aircraft bleed air duct (2) can be obtained.

4. The intelligent casing system for aircraft high temperature bleed air pipeline according to claim 1, characterized in that: Optical fiber connectors are provided at both ends of the temperature monitoring ring (4), and the first optical fiber grating temperature sensor (3) and the second optical fiber grating temperature sensor (5) are connected via the optical fiber connector (7); The temperature monitoring ring (4) is an articulated monitoring ring. The second fiber grating temperature sensor (5) is reciprocatingly attached to the inner wall of the articulated monitoring ring. The temperature monitoring ring (4) is locked by a second buckle (4.1). The second fiber grating temperature sensor (5) monitors the temperature at the corresponding position of the aircraft bleed air duct (2) joint through each grating, thereby obtaining distributed temperature data at the aircraft bleed air duct (2) joint.

5. The intelligent casing system for aircraft high temperature bleed air pipeline according to claim 1, characterized in that: The specific method of the bleed air duct temperature field construction module to construct the bleed air duct temperature field model using an interpolation-based temperature field restoration algorithm based on the distributed temperature data of the aircraft bleed air duct (2) pipe body and the distributed temperature data at the joint of the aircraft bleed air duct (2) is as follows: Assume that the temperature of any point on the inner wall of the insulating sleeve (1) and the temperature monitoring ring (4) is T(x, y, z), (x, y, z)∈A, A is a set consisting of all points on the inner wall of the insulating sleeve (1) and the temperature monitoring ring (4), and assume that the total number of gratings of the first fiber grating temperature sensor (3) and the second fiber grating temperature sensor (5) is n. At time t, the temperature data T(x) of n points on the inner wall of the insulating sleeve (1) and the temperature monitoring ring (4) are obtained. i ,y i , z i ), (x i ,y i , z i )∈A, i=1, 2, ..., n, use these n points as sample functions and define the interpolation function Where r = || xx i ,yy i ,zz i || represents the distance between the midpoint (x, y, z) of the insulation sleeve (1) and the temperature monitoring ring (4) and the point (x i ,y i , z i )’s Euclidean distance, w i Weight coefficient, φ is the radial basis function, Where α is the shape parameter of the radial basis function, φ(r) is the basis function, and e is a natural constant; function Satisfy the interpolation conditions: Substituting n sample points into the above formula, we have: make The above formula can be simplified to obtain the airway duct temperature field model: T=wφ。 6. The intelligent casing system for aircraft high temperature bleed air pipeline according to claim 5, characterized in that: By solving the linear equations, we get the linear combination coefficient w and put w into The interpolation model is obtained, which is the airway duct temperature field model.

7. The intelligent casing system for aircraft high temperature bleed air pipeline according to claim 5, characterized in that: The area where the temperature gradient in the bleed air duct temperature field model is greater than the threshold is the bleed air leakage area. The temperature at the point where the temperature gradient is greater than the threshold is taken as the isotherm, and its isotherm contour is used to characterize the size and shape of the bleed air leakage.

8. A method for monitoring bleed air leakage in a high temperature bleed air pipeline of an aircraft based on the system of claim 1, characterized in that: It includes the following steps: The first fiber grating temperature sensor (3) monitors the temperature at corresponding positions of the aircraft bleed air duct (2) through each grating, thereby obtaining distributed temperature data of the aircraft bleed air duct (2) body, and the second fiber grating temperature sensor (5) monitors the temperature at corresponding positions of the aircraft bleed air duct (2) joint through each grating, thereby obtaining distributed temperature data of the aircraft bleed air duct (2) joint; A bleed air duct temperature field model is constructed based on distributed temperature data of the aircraft bleed air duct body (2) and distributed temperature data at a joint of the aircraft bleed air duct (2) using an interpolation-based temperature field restoration algorithm, the bleed air duct temperature field model is used to obtain temperature data of each point of the aircraft bleed air duct (2), and the bleed air leakage situation is determined using the temperature data of each point of the aircraft bleed air duct (2).

9. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method described in claim 8 are implemented.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the method according to claim 8 are implemented.

Images