Internal temperature strain measurement method in forming process of winding spray pipe and winding spray pipe

Abstract

The invention relates to a winding spray pipe forming process internal temperature strain measurement method and a winding spray pipe, and the method comprises the steps: winding first winding cloth on the surface of a winding core mold, laying a grating fiber sensor between the first winding cloth to form an inner layer structure, and enabling a part of the grating fiber sensor to be located in the inner layer structure, the other part extends out of the inner layer structure; vacuumizing the inner-layer structure, then transferring the inner-layer structure into an autoclave for curing, and carrying out a conduction test on the grating optical fiber sensor; the inner layer structure is taken out of the autoclave, second winding cloth is used for winding the surface of the inner layer structure, a grating optical fiber sensor is laid between the second winding cloth, a spray pipe winding piece is formed, part of the grating optical fiber sensor is located in the second winding cloth, and the other part of the grating optical fiber sensor extends out of the second winding cloth; vacuumizing the spray pipe winding piece, then moving the spray pipe winding piece into an autoclave for curing, and performing a conduction test on the grating fiber sensor; and the spray pipe winding piece is taken out of the autoclave for demolding.

Description

Technical Field

[0001] This application relates to the field of winding nozzle forming, and particularly to a method for measuring internal temperature strain during the winding nozzle forming process and a winding nozzle. Background Art

[0002] The integrally wound formed nozzle adopts an additive manufacturing method, which is different from the traditional typical multi-component assembled nozzle. It uses a cloth tape winding and curing method, eliminating the obvious interface formed by bonding of multiple nozzle components, and effectively reducing the failure risk caused by flame leakage during the nozzle operation. However, the curing process experienced during the nozzle forming process is a complex physical and chemical reaction process. Due to multiple factors such as the chemical shrinkage of the resin, the difference in the thermal expansion coefficients of the fiber cloth and the matrix resin, and the material of the winding mandrel, residual stress (referred to as curing residual stress) will be generated during the curing process of the nozzle structure. In addition, during the solid rocket engine test process, due to factors such as high-temperature and high-pressure gas and sealing, it is difficult to measure the internal temperature rise during the operation of the engine nozzle. After the test, the carbonization degree of the nozzle obtained by dissection often contains the after-effect heat transfer carbonization effect at the end of the engine operation, which cannot intuitively reflect the structural heat transfer situation of the nozzle during operation, and is even less able to reflect parameters such as structural stress during the operation process. Therefore, how to adopt an effective and feasible measurement scheme to obtain the internal state during the forming and operation of the integrally wound nozzle of the engine, and provide a basis for optimizing the manufacturing process parameters and structural optimization of the subsequent nozzle, is of great significance. Summary of the Invention

[0003] This application provides a method for measuring internal temperature strain during the winding nozzle forming process and a winding nozzle, which can solve the problem in the related art that the current winding nozzle cannot collect the structural heat transfer situation of the nozzle in a timely and accurate manner during the test measurement process.

[0004] In a first aspect, an embodiment of this application provides a method for measuring internal temperature strain during the winding nozzle forming process, which includes:

[0005] Using a first winding cloth to wind on the surface of the winding mandrel, and laying a fiber Bragg grating sensor between the first winding cloths to form an inner layer structure, with part of the fiber Bragg grating sensor located inside the inner layer structure and the other part extending outside the inner layer structure;

[0006] After evacuating the inner layer structure, move it into a autoclave for curing, and conduct a conduction test on the fiber Bragg grating sensor;

[0007] Take out the inner layer structure from the autoclave, use a second winding cloth to wind on the surface of the inner layer structure, and lay a fiber Bragg grating sensor between the second winding cloths to form a nozzle winding part, with part of the fiber Bragg grating sensor located inside the second winding cloth and the other part extending outside the second winding cloth;

[0008] After evacuating the nozzle winding, move it into an autoclave for curing, and conduct a conduction test on the fiber Bragg grating (FBG) sensor.

[0009] Take out the nozzle winding from the autoclave and demold it to complete the forming of the wound nozzle.

[0010] In some embodiments, when laying the FBG sensor, it is laid circumferentially and axially along the surface of the winding mandrel.

[0011] In some embodiments, when the first winding cloth is wound to a first set thickness, the FBG sensor is laid on the surface of the first winding cloth.

[0012] When the second winding cloth is wound to a second set thickness, the FBG sensor is laid on the surface of the second winding cloth.

[0013] In some embodiments, the FBG sensors in the nozzle winding are respectively located inside the first winding cloth and inside the second winding cloth.

[0014] In some embodiments, conducting the conduction test through the FBG sensor specifically includes:

[0015] Lead the FBG sensor out of the autoclave.

[0016] Connect the FBG sensor to a modem.

[0017] When curing the nozzle winding in the autoclave, collect the signals of the FBG sensor to collect the internal temperature and strain signals of the material during the curing process of the nozzle winding.

[0018] In some embodiments, leading the FBG sensor out of the autoclave specifically includes:

[0019] Thermally connect the FBG sensor to the lead-out optical fiber line of the autoclave to realize the lead-out of the FBG sensor.

[0020] In some embodiments, the first winding cloth includes one or more of carbon cloth, phenolic-silicone cloth, and phenolic cloth.

[0021] In some embodiments, the second winding cloth includes one or more of carbon fiber prepreg and epoxy unidirectional prepreg.

[0022] In some embodiments, when evacuating, use a sleeve to protect the FBG sensor.

[0023] In a second aspect, an embodiment of the present application provides a wound nozzle obtained by using the internal temperature and strain measurement method for the wound nozzle forming process as described above.

[0024] The beneficial effects brought by the technical solution provided in the embodiment of the present application include:

[0025] The embodiment of the present application provides a method for measuring internal temperature and strain during the forming process of a wound nozzle and a wound nozzle. By placing a grating optical fiber sensor during the winding and laying process of the nozzle, and leading out the port of the grating optical fiber sensor, the optical wave signal of the grating optical fiber sensor changing with time can be obtained in a timely manner during the curing and working processes of the nozzle. Through modulation and demodulation, the temperature and strain data inside the wound nozzle can be intuitively reflected, so as to realize the real-time monitoring of the internal state of the wound nozzle. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0027] Figure 1 It is a schematic diagram of the test scheme of the grating optical fiber sensor provided by the embodiment of the present application;

[0028] Figure 2 It is a schematic diagram of the measuring point arrangement scheme of the grating optical fiber sensor during the winding forming process of the nozzle provided by the embodiment of the present application;

[0029] Figure 3 It is a schematic diagram of the measuring point arrangement scheme of the grating optical fiber sensor during the laying forming process of the nozzle structure provided by the embodiment of the present application;

[0030] Figure 4 It is a flowchart of the method for measuring internal temperature and strain during the forming process of the wound nozzle provided by the embodiment of the present application.

[0031] In the figure: 1. Nozzle winding part; 2. Grating optical fiber sensor; 3. Modem; 4. Terminal processor; 5. Winding mandrel; 6. First winding cloth; 7. Autoclave; 8. Second winding cloth. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] In order to enable those skilled in the art to better understand the solution of the present application, the following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, rather than all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present application.

[0033] See Figures 1 to 4, embodiments of the present application provide a method for measuring internal temperature and strain during the forming process of a wound nozzle and a wound nozzle, which can solve the problem in the related art that the current wound nozzle cannot collect the heat transfer situation of the nozzle structure in a timely and accurate manner during the test measurement process.

[0034] In a first aspect, embodiments of the present application provide a method for measuring internal temperature and strain during the forming process of a wound nozzle, which includes:

[0035] Step 101: Wind the first winding cloth 6 on the surface of the winding mandrel 5, and lay the grating optical fiber sensor 2 between the first winding cloths 6 to form an inner layer structure. Part of the grating optical fiber sensor 2 is located inside the inner layer structure, and the other part extends outside the inner layer structure;

[0036] Step 102: After evacuating the inner layer structure, move it into the autoclave 7 for curing, and conduct a conduction test on the grating optical fiber sensor 2;

[0037] Step 103: Take out the inner layer structure from the autoclave 7, wind the second winding cloth 8 on the surface of the inner layer structure, and lay the grating optical fiber sensor 2 between the second winding cloths 8 to form a nozzle winding part 1. Part of the grating optical fiber sensor 2 is located inside the second winding cloth 8, and the other part extends outside the second winding cloth 8;

[0038] Step 104: After evacuating the nozzle winding part 1, move it into the autoclave 7 for curing, and conduct a conduction test on the grating optical fiber sensor 2;

[0039] Step 105: Take out the nozzle winding part 1 from the autoclave 7 and demold it to complete the forming of the wound nozzle.

[0040] In the present application, by placing the grating optical fiber sensor 2 during the winding and laying process of the nozzle, and leading out the port of the grating optical fiber sensor 2, the optical wave signal of the grating optical fiber sensor 2 changing with time can be obtained in a timely manner during the curing and working processes of the nozzle. Through modulation and demodulation, the temperature and strain data inside the wound nozzle can be intuitively reflected, so as to realize the real-time monitoring of the internal state of the wound nozzle.

[0041] In this embodiment, when manufacturing the wound nozzle, the inner layer structure is first wound on the winding mandrel 5. The inner layer structure is the diffuser section of the nozzle. The main function of the diffuser section of the nozzle is to convert the high-speed kinetic energy obtained by the fluid at the throat into pressure energy. In the diffuser section of the nozzle, as the cross-section gradually increases, the velocity of the fluid gradually decreases while the pressure gradually increases. This conversion enables the fluid to have a higher static pressure and a lower flow velocity at the nozzle outlet, thereby improving the thrust efficiency of the nozzle. The material of the diffuser section of the nozzle needs to be ablative-resistant and heat-insulating to protect the inside of the wound nozzle from the erosion and ablation of high-temperature gas. Therefore, in this embodiment, the first winding cloth 6 for setting the inner layer structure includes one or more of carbon cloth, phenolic-silicone cloth, and phenolic cloth. Among them, carbon cloth is a carbon fiber fabric, usually obtained by carbonizing certain fibers (such as polyacrylonitrile fibers) at high temperature in an air-free environment, and has excellent tensile and fracture resistance properties; phenolic-silicone cloth is a material composed of high-silica fiber cloth and phenolic resin. Its manufacturing process generally includes coating phenolic resin on high-silica fiber cloth and undergoing steps such as high-temperature heating and curing. Phenolic-silicone cloth has good flame retardancy, can self-extinguish at high temperature, has good high-temperature resistance, can maintain stable properties for a long time at a temperature above 1000 °C, and has good ablative resistance and heat-insulating properties, and is commonly used in thermal protection systems; phenolic cloth refers to a composite material formed by coating phenolic resin on the surface of cotton cloth and undergoing high-temperature heating and curing. Phenolic cloth is hard and wear-resistant, has a high surface hardness and wear resistance, and also has high heat resistance and insulation properties.

[0042] See Figure 2 As shown, the first winding cloth 6 wound on the surface of the winding mandrel 5 can be carbon cloth, and phenolic prepreg can also be selected. The first winding cloth 6 of the second winding layer is wound on the surface of the first winding cloth 6 of the first winding layer. The first winding cloth 6 can be selected from phenolic-silicone cloth or phenolic prepreg. It should be noted that phenolic prepreg has good plasticity and processability, can easily complete processes such as processing and forming, and can meet various process manufacturing requirements; in addition, after phenolic resin is cured, it forms a three-dimensional cross-linked structure, making phenolic prepreg have excellent heat resistance and high strength, and can maintain stable properties in a high-temperature environment; at the same time, phenolic materials can maintain a high char yield when burning, and can effectively absorb free radicals generated during high-temperature degradation, slowing down the oxidation of the material, thereby showing extremely excellent flame retardancy.

[0043] According to requirements, multiple layers of the first winding cloth 6 can be provided for the inner layer structure. The number of layers and the materials used for each layer of the first winding cloth 6 are not limited in this embodiment.

[0044] When winding the inner layer structure, the grating optical fiber sensor 2 needs to be laid in the first winding cloth 6. It should be noted that when laying the grating optical fiber sensor 2, it is laid circumferentially and axially along the surface of the winding mandrel 5. As Figure 2 shown, in Figure 2 , point A represents the grating optical fiber sensor 2 arranged circumferentially, and the horizontal line B represents the grating optical fiber sensor 2 arranged axially. In addition, part of the grating optical fiber sensor 2 needs to be located inside the inner layer structure, and the other part needs to extend outside the inner layer structure, so as to realize the implantation of the grating optical fiber sensor 2 in the circumferential, axial and between winding layers of the inner layer structure. Among them, the grating optical fiber sensor 2 includes a temperature optical fiber sensor and a strain optical fiber sensor.

[0045] Among them, the grating optical fiber sensor 2 in the nozzle winding part 1 is located inside the first winding cloth 6: when each layer of the first winding cloth 6 is wound to the first set thickness, the grating optical fiber sensor 2 is laid on the surface of the first winding cloth 6, and then continue to wind to wrap the grating optical fiber sensor 2 inside the first winding cloth 6.

[0046] The following further describes the present invention in detail with reference to the drawings: during the winding and curing process of the nozzle, a carbon cloth or phenolic prepreg with a width of L1 is wound on the winding mandrel 5. At the winding radius R (determined according to the measuring point position), the grating optical fiber sensor 2 is arranged, and the optical fiber is led out along the winding ring surface. Before leading out, it is ensured that a high silica prepreg or phenolic prepreg with a width of L2 is wound to the same radius R, which is convenient for leading out the grating optical fiber sensor 2 of the inner layer structure. The grating optical fiber sensor 2 is arranged circumferentially and axially according to the test direction.

[0047] After successively completing the production of the first winding cloth 6 and the synchronous implantation of the grating optical fiber sensor 2, finally, the overall hot pressing and curing process operations such as bagging and vacuum pumping of the winding mandrel 5 and the inner layer structure are carried out:

[0048] Perform step 102: evacuate the inner layer structure and then move it into the autoclave 7 for curing, and conduct a conduction test on the grating optical fiber sensor 2.

[0049] When evacuating, use a sleeve to protect the grating optical fiber sensor 2, that is, pay attention to protecting the grating optical fiber sensor 2 during the bagging and vacuum pumping process to avoid breakage. After evacuation, conduct a conduction test on each measuring point to confirm the survival of the grating optical fiber sensor 2.

[0050] The conduction test is carried out through the grating optical fiber sensor 2, which specifically includes: first, lead out the grating optical fiber sensor 2 from the autoclave 7; then connect the grating optical fiber sensor 2 to the modem 3; finally, when curing the nozzle winding part 1 in the autoclave 7, collect the signals of the grating optical fiber sensor 2 to collect the internal temperature and strain signals of the material during the curing process of the nozzle winding part 1.

[0051] Among them, leading out the fiber Bragg grating sensor 2 from the autoclave 7 specifically includes: thermally connecting the fiber Bragg grating sensor 2 with the lead-out optical fiber line of the autoclave 7 to achieve the lead-out of the fiber Bragg grating sensor 2. The fiber Bragg grating sensor 2 is led out from the inner layer structure to be measured inside, and then professional thermal connection treatment is carried out through the lead-out optical fiber line in the autoclave 7. This process ensures a firm connection between the fiber Bragg grating sensor 2 and the lead-out optical fiber line, thus successfully leading out the fiber Bragg grating sensor 2. Among them, during the process of connecting the fiber Bragg grating sensor 2 with the lead-out optical fiber line of the autoclave 7, thermal connection is a technology that heats the end face of the fiber Bragg grating sensor 2 to make it melt and connect together, which can ensure a firm connection between the optical fibers and stable signal transmission.

[0052] After leading out the fiber Bragg grating sensor 2 from the autoclave 7, connect the fiber Bragg grating sensor 2 with the modem 3 and transmit the signal to the terminal processor 4. When curing the nozzle winding part 1 in the autoclave 7, that is, during the process of the autoclave 7 heating up and pressurizing for curing, by collecting the signal of the fiber Bragg grating sensor 2, the internal temperature and strain signals of the material during the curing process of the nozzle winding part 1 are collected.

[0053] Based on the above embodiments, in this embodiment, step 103: Take out the inner layer structure from the autoclave 7, wind the second winding cloth 8 on the surface of the inner layer structure, and lay the fiber Bragg grating sensor 2 between the second winding cloths 8 to form the nozzle winding part 1. Part of the fiber Bragg grating sensor 2 is located inside the second winding cloth 8, and the other part extends outside the second winding cloth 8. Specifically:

[0054] After winding the inner layer structure, cure it, and then wind the outer layer structure on the surface of the inner layer structure. The outer layer structure is the structure laying part. The structure laying part for winding the nozzle involves multiple key components, and each part is laid and connected through specific materials and processes to ensure the performance and service life of the nozzle.

[0055] The second winding cloth 8 of the outer layer structure includes one or more of carbon fiber prepreg and epoxy unidirectional prepreg. Among them, carbon fiber prepreg, also known as carbon fiber prepreg cloth, is a composite material processed by processes such as coating film, hot pressing, cooling, film covering, and winding of reinforcing materials (carbon fiber yarn, epoxy resin, release paper, etc.). It combines the high strength and high modulus of carbon fiber and the good processing performance of the resin matrix, and has the advantages of light weight, high strength, corrosion resistance, insulation, etc.; Epoxy unidirectional prepreg is a composite material intermediate material obtained by impregnating epoxy resin with unidirectionally arranged reinforcing fibers and going through process steps such as drying. During the preparation process, the epoxy resin is fully dissolved and evenly dispersed between the fibers to form a highly impregnated composite material.

[0056] See Figure 3 As shown, the surface of the inner structure is wound with carbon fiber prepreg or epoxy unidirectional prepreg. When winding the outer structure, it is necessary to lay the grating optical fiber sensor 2 between the second winding cloth 8. It should be noted that when laying the grating optical fiber sensor 2, it is laid circumferentially and axially along the surface of the winding mandrel 5. In Figure 3 the figure, the points in the outer structure represent the grating optical fiber sensors 2 arranged circumferentially, and the horizontal lines represent the grating optical fiber sensors 2 arranged axially. In addition, part of the grating optical fiber sensor 2 needs to be located inside the outer structure, and the other part needs to extend outside the outer structure, so as to realize the implantation of the grating optical fiber sensor 2 in the circumferential, axial and interlayer directions of the outer structure. The grating optical fiber sensor 2 here also includes a temperature optical fiber sensor and a strain optical fiber sensor.

[0057] Among them, the grating optical fiber sensor 2 in the outer structure is located inside the second winding cloth 8: when each layer of the second winding cloth 8 is wound to the second set thickness, the grating optical fiber sensor 2 is laid on the surface of the second winding cloth 8, and then the winding continues to wrap the grating optical fiber sensor 2 inside the second winding cloth 8.

[0058] Then perform step 104: evacuate the nozzle winding part 1 and move it into the autoclave 7 for curing, and conduct a conduction test on the grating optical fiber sensor 2.

[0059] The same as step 102, when evacuating, use a sleeve to protect all the grating optical fiber sensors 2, that is, pay attention to protecting the grating optical fiber sensors 2 during the bagging evacuation process to avoid breakage. After evacuation, conduct a conduction test on each measuring point to confirm the survival of all the grating optical fiber sensors 2.

[0060] The conduction test is carried out through the grating optical fiber sensor 2, which specifically includes: first, lead out all the grating optical fiber sensors 2 from the autoclave 7; then connect all the grating optical fiber sensors 2 to the modem 3; finally, when curing the nozzle winding part 1 in the autoclave 7, collect the signals of all the grating optical fiber sensors 2 to collect the internal temperature and strain signals of the material during the curing process of the nozzle winding part 1.

[0061] Among them, all the fiber Bragg grating sensors 2 are led out of the autoclave 7, which specifically includes: thermally connecting all the fiber Bragg grating sensors 2 with the lead-out optical fiber line of the autoclave 7 to realize the lead-out of all the fiber Bragg grating sensors 2. All the fiber Bragg grating sensors 2 are led out from the inner layer structure to be measured, and then professional thermal connection treatment is carried out through the lead-out optical fiber line in the autoclave 7. This process ensures a firm connection between all the fiber Bragg grating sensors 2 and the lead-out optical fiber line, thus successfully leading out all the fiber Bragg grating sensors 2. Among them, during the process of connecting all the fiber Bragg grating sensors 2 with the lead-out optical fiber line of the autoclave 7, thermal connection is a technology that heats the end faces of all the fiber Bragg grating sensors 2 to make them melt and connect together, which can ensure a firm connection between the optical fibers and stable signal transmission.

[0062] After all the fiber Bragg grating sensors 2 are led out of the autoclave 7, all the fiber Bragg grating sensors 2 are connected to the modem 3, and the signals are transmitted to the terminal processor 4. When curing the nozzle winding part 1 in the autoclave 7, that is, during the process of heating and pressurizing the autoclave 7 for curing, by collecting the signals of all the fiber Bragg grating sensors 2, the internal temperature and strain signals of the material during the curing process of the nozzle winding part 1 are collected.

[0063] As Figure 3 shown, T700 or epoxy prepreg is laid on the cured carbon cloth - high silica cloth or phenolic material. The prepreg is laid in cycles at a specific laying angle. When the laying thickness reaches a specific thickness, fiber Bragg grating sensors 2 are arranged at different positions, and the fiber Bragg grating sensors 2 are led out along the laying surface. The fiber Bragg grating sensors 2 are further arranged circumferentially and axially according to the test direction. The laying and forming of the second winding cloth 8 and the implantation of the fiber Bragg grating sensors 2 are completed in sequence. Finally, the overall bagging and vacuum pumping and other autoclave curing process operations are carried out on the winding mandrel 5 with a bag. During the bagging and vacuum pumping process, pay attention to protecting the optical fiber to avoid breakage. After vacuum pumping, conduction tests are carried out on each measuring point to confirm the survival of the fiber Bragg grating.

[0064] After the nozzle is produced and during storage, interface parameter monitoring can be carried out through the led-out fiber Bragg grating sensors 2. During the operation of the wound nozzle, by leading out the fiber Bragg grating sensors 2 and connecting the acquisition and decoupling equipment in advance, the temperature and strain changes at different positions (measuring points of the fiber Bragg grating sensors 2) inside the structure during the operation of the wound nozzle can be realized, so as to realize the real-time and intuitive understanding of the temperature and strain conditions inside the structure of the wound nozzle, breaking through the non-intuitive detection of only understanding the surface conditions of the structure through the temperature and strain sensors on the surface of the wound nozzle. After the operation of the wound nozzle is completed, data collection can be continued to obtain the post-effect heat transfer process and structural strain conditions of the nozzle.

[0065] It should be noted that, in addition to the grating optical fiber sensor 2, conventional sensors can also be provided on the inner structure and the outer structure for dotting and testing on the surface of the winding cloth; thin film sensors can also be used and implanted inside the winding cloth for testing, which can theoretically achieve the purpose of monitoring the temperature and strain during the nozzle curing process and the test run process. However, compared with the grating optical fiber sensor 2, there are problems such as narrow temperature adaptability, low viability, and poor test stability. In addition, this type of sensor is relatively large and has a greater impact on the internal quality of the product forming. Therefore, preferably, the grating optical fiber sensor 2 is pasted on the nozzle winding part 1.

[0066] Finally, perform step 105: After the nozzle winding part 1 is cured, take it out of the autoclave 7 for demolding to complete the forming of the wound nozzle.

[0067] After the nozzle winding part 1 is cured in the autoclave 7, cut the through-wall optical fiber interface of the autoclave 7, and take out the cured nozzle winding part 1, and protect the led-out grating optical fiber sensor 2 during the taking-out process. After taking out, perform demolding treatment to remove the winding core mold 5 and present the final form of the wound nozzle.

[0068] After the wound nozzle is formed, the internal parameters of the cured product are monitored by thermally connecting the grating optical fiber sensor 2 on it with other optical fibers. Similarly, tests can be carried out during the test run process. During the test, the health status of the wound nozzle will be monitored in real time, with the functions of monitoring the debonding between the winding layers and the internal interface of the body, internal strain, and temperature, improving the monitoring accuracy and breadth, so as to provide a judgment basis for the internal quality and working state of the engine nozzle.

[0069] The wound nozzle of the present application can be applied to the measurement of the internal parameters of the engine nozzle: The grating optical fiber sensor 2 is provided in the wound nozzle of the present application, with a fine diameter (0.2 mm), and has the characteristics of miniaturization, multi-functionality, high sensitivity, safety, stability, and anti-interference. Implanting it inside the nozzle does not affect the nozzle structure and manufacturing; it can not only measure the internal structure strain and temperature during the nozzle working process, but also measure the temperature and strain during the preparation and curing process of the wound nozzle, and can measure the curing residual stress of the nozzle, with high test accuracy, safety and reliability, and can monitor the nozzle state in real time; through the analysis of the collected data, it can provide data support for the process parameter and structure optimization during the preparation process of the wound nozzle; effectively improving the test and experimental level of the engine nozzle.

[0070] In a second aspect, an embodiment of the present application provides a wound nozzle obtained by using the internal temperature and strain measurement method for the wound nozzle forming process provided in any one of the above embodiments of the present application.

[0071] In this application, by placing the fiber Bragg grating (FBG) sensor 2 during the winding and laying process of the nozzle, and leading out the ports of the FBG sensor 2, the optical wave signals of the FBG sensor 2 changing with time can be obtained in a timely manner during the curing and working processes of the nozzle. Through modulation and demodulation, the temperature and strain data inside the wound nozzle can be intuitively reflected, so as to realize the real-time monitoring of the internal state of the wound nozzle.

[0072] In the description of this application, it should be noted that the orientation or positional relationship indicated by terms such as "upper" and "lower" is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to this application. Unless otherwise clearly specified and defined, the terms "mounted", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0073] It should be noted that in this application, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprising", "including" or any other variation thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including a..." does not exclude the existence of additional identical elements in the process, method, article or device including the said element.

[0074] The above description is only the specific implementation manners of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be obvious to those skilled in the art. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application will not be limited to these embodiments shown herein, but will be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A method for measuring internal temperature and strain during the forming process of a coiled nozzle, characterized in that, It includes: Using the first winding cloth (6) to wind on the surface of the winding mandrel (5), and laying the grating optical fiber sensor (2) between the first winding cloth (6) to form an inner layer structure. Part of the grating optical fiber sensor (2) is located inside the inner layer structure, and the other part extends outside the inner layer structure. After evacuating the inner layer structure, move it into the autoclave (7) for curing, and conduct a conduction test on the grating optical fiber sensor (2). Take out the inner layer structure from the autoclave (7), use the second winding cloth (8) to wind on the surface of the inner layer structure, and lay the grating optical fiber sensor (2) between the second winding cloth (8) to form a nozzle winding part (1). Part of the grating optical fiber sensor (2) is located inside the second winding cloth (8), and the other part extends outside the second winding cloth (8). After evacuating the nozzle winding part (1), move it into the autoclave (7) for curing, and conduct a conduction test on the grating optical fiber sensor (2). Take out the nozzle winding part (1) from the autoclave (7) for demolding to complete the forming of the winding nozzle.

2. The internal temperature and strain measurement method during the winding nozzle forming process according to claim 1, characterized in that: When laying the grating optical fiber sensor (2), lay it circumferentially and axially along the surface of the winding mandrel (5).

3. The internal temperature and strain measurement method during the forming process of the winding nozzle as described in claim 1, characterized in that: When the first winding cloth (6) is wound to a first set thickness, lay the grating optical fiber sensor (2) on the surface of the first winding cloth (6). When the second winding cloth (8) is wound to a second set thickness, lay the grating optical fiber sensor (2) on the surface of the second winding cloth (8).

4. The internal temperature and strain measurement method during the forming process of the winding nozzle as described in claim 3, characterized in that: The grating optical fiber sensors (2) in the nozzle winding part (1) are respectively located inside the first winding cloth (6) and the second winding cloth (8).

5. The internal temperature and strain measurement method during the winding nozzle forming process according to claim 1, characterized in that Conducting the conduction test through the grating optical fiber sensor (2) specifically includes: Leading out the grating optical fiber sensor (2) from the autoclave (7). Connecting the grating optical fiber sensor (2) to the modem (3). When curing the nozzle winding part (1) in the autoclave (7), collect the signals of the grating optical fiber sensor (2) to collect the internal temperature and strain signals of the material during the curing process of the nozzle winding part (1).

6. The internal temperature and strain measurement method during the winding nozzle forming process according to claim 5, characterized in that, Leading out the grating optical fiber sensor (2) from the autoclave (7) specifically includes: Thermally connecting the grating optical fiber sensor (2) to the lead-out optical fiber line of the autoclave (7) to realize the leading out of the grating optical fiber sensor (2).

7. The internal temperature and strain measurement method during the forming process of the winding nozzle as described in claim 1, characterized in that: The first winding cloth (6) includes one or more of carbon cloth, phenolic - high silica cloth, and phenolic cloth.

8. The internal temperature and strain measurement method during the forming process of the winding nozzle as described in claim 1, characterized in that: The second winding cloth (8) includes one or more of carbon fiber prepreg and epoxy unidirectional prepreg.

9. The internal temperature and strain measurement method during the forming process of the winding nozzle as described in claim 1, characterized in that: When evacuating, use a sleeve to protect the grating optical fiber sensor (2).

10. A coiled nozzle, characterized in that, Obtained by using the internal temperature and strain measurement method for the winding nozzle forming process described in any one of claims 1-9.

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