Distributed optical fiber-oriented multi-physical field joint calibration method, system, equipment and medium

Abstract

The embodiment of the invention provides a distributed optical fiber-oriented multi-physical field joint calibration method, system and device, and a medium, and belongs to the technical field of distributed optical fibers. The method comprises the following steps: acquiring multi-source response quantity and physical property information based on the along-line deployment information of the distributed optical fiber; constructing a physical property segmentation structure containing segmented physical property parameters based on the physical property information, and inputting the multi-source response quantity and the physical property segmentation structure into a multi-physical field joint calibration model; based on the laying state of the distributed optical fiber, obtaining the laying state variable quantity, and mapping the laying state variable quantity into the time correction quantity of the physical property segmentation structure to update the multi-physical field joint calibration model; and on the basis of the updated multi-physics field joint calibration model, performing along-line integration processing on the segmented physical quantity calculation result, generating along-line physical quantity distribution, and outputting the along-line physical quantity distribution as a joint calibration result. According to the scheme, more coherent and time-varying consistent distributed optical fiber along-line physical quantity distribution is generated under the conditions of multi-source response coupling and along-line physical property change.

Description

Technical Field

[0001] This invention relates to the field of distributed optical fiber technology, and more specifically to a multi-physics joint calibration method, system, device, and medium for distributed optical fibers. Background Technology

[0002] Distributed fiber optic sensing has been widely deployed in the field of temperature and stress monitoring. This type of sensing typically relies on three optical scattering mechanisms: Raman scattering, which primarily reflects temperature changes; Brillouin shift, which is affected by both temperature and stress; and Rayleigh scattering, which is more sensitive to stress. Within the same fiber, these three responses often coexist, causing temperature and stress to couple in the measurement signal. Traditional separation models based on fixed proportionality coefficients are prone to shifting during long-term field use.

[0003] In real-world engineering environments, optical fibers often exhibit various laying methods along their routes, such as loose tubes, tight-coupled tubes, or metal sheaths, resulting in significant differences in heat diffusion capabilities and stress transfer conditions across different sections. Existing calibration techniques are mostly based on the assumption of uniform optical fiber properties to construct unified parameters, making it difficult to cover the segmental differences caused by mixed laying of multiple sections.

[0004] Meanwhile, optical fibers undergo changes in their laying condition during long-term service, such as settlement, loosening, or periodic loads. These changes affect the coupling between the fiber and the environment, causing the initial calibration parameters to drift over time. Existing methods lack the ability to dynamically compensate for these time-varying changes, gradually leading to inaccuracies in long-term multiphysics monitoring scenarios. Summary of the Invention

[0005] The purpose of this invention is to provide a multi-physics joint calibration method, system, device and medium for distributed optical fibers, so as to at least solve the problems of high coupling degree of multi-source optical response, failure to distinguish the differences in physical properties along the line and drift of calibration parameters caused by changes in the laying state over time in the prior art.

[0006] To achieve the above objectives, a first aspect of the present invention provides a multi-physics joint calibration method for distributed optical fibers. The method includes: acquiring multi-source response quantities and physical property information based on the deployment information along the distributed optical fiber; constructing a physical property segmentation structure containing segmented physical property parameters based on the physical property information, and inputting the multi-source response quantities and the physical property segmentation structure into a multi-physics joint calibration model to generate segmented physical quantity calculation results; acquiring the laying state change quantity based on the laying state of the distributed optical fiber, and mapping the laying state change quantity to a time correction quantity of the physical property segmentation structure to update the multi-physics joint calibration model; performing along-line integration processing on the segmented physical quantity calculation results based on the updated multi-physics joint calibration model to generate a along-line physical quantity distribution and output it as a joint calibration result.

[0007] Optionally, multi-source response quantities and physical property information are obtained based on the deployment information along the distributed optical fiber, including: extracting Raman response quantities for characterizing temperature response, Brillouin frequency shift response quantities for characterizing temperature and stress mixed response, and Rayleigh scattering response quantities for characterizing stress response based on the deployment information along the distributed optical fiber, and using the Raman response quantities, Brillouin frequency shift response quantities, and Rayleigh scattering response quantities as multi-source response quantities; and extracting physical property information for characterizing optical fiber material, coating structure, and laying method based on the deployment information along the fiber.

[0008] Optionally, constructing a property segmentation structure containing segmented property parameters based on the property information includes: dividing the distributed optical fiber along its length into segments based on the property information to obtain property segments corresponding to each segment; extracting thermal diffusion parameters, axial stress coupling parameters, and transverse shear coupling parameters based on the optical fiber material, coating structure, and laying method contained in each property segment, and combining the thermal diffusion parameters, axial stress coupling parameters, and transverse shear coupling parameters to form segmented property parameters; and writing the segmented property parameters into the corresponding property segments to construct a property segmentation structure containing multiple property segments and their corresponding segmented property parameters.

[0009] Optionally, the multi-source response quantities and the segmented material property structure are input into a multi-physics joint calibration model to generate segmented physical quantity calculation results. This includes: determining the segmented material property parameters corresponding to each segment based on the segmented material property structure, and writing the segmented material property parameters into the segmented calculation structure of the multi-physics joint calibration model; performing position matching on the multi-source response quantities corresponding to each segment based on the input requirements of the segmented calculation structure, and writing the matched multi-source response quantities into the multi-physics joint calibration model; performing a joint solution operation of temperature and stress quantities based on the written segmented material property parameters and the multi-source response quantities to obtain the temperature and stress calculation quantities corresponding to each segment; and writing the temperature and stress calculation quantities into the segmented material property structure according to the segmented position to form segmented physical quantity calculation results.

[0010] Optionally, based on the written segmented physical property parameters and the multi-source response quantities, a joint solution operation for temperature and stress quantities is performed to obtain the temperature and stress solutions for each segment. This includes: determining the solution coefficients for characterizing temperature-sensitive and stress-sensitive terms based on the segmented physical property parameters, and configuring the solution coefficients and the multi-source response quantities for each segment in a one-to-one correspondence; performing matrix solving processing based on the input-configured solution coefficients and multi-source response quantities to separate the temperature-sensitive and stress-sensitive components for each segment, thereby obtaining the temperature solution for characterizing temperature changes and the stress solution for characterizing stress changes.

[0011] Optionally, obtaining the laying state change based on the laying state of the distributed optical fiber, and mapping the laying state change to the time correction amount of the physical property segment structure to update the multiphysics joint calibration model, includes: extracting laying state information characterizing the contact form, constraint method, and burial depth conditions based on the laying state along the distributed optical fiber, and determining the laying state change amount corresponding to each segment based on the laying state information; generating a time correction amount reflecting the time change of the segment physical property parameters based on the laying state change amount, and correlating the time correction amount with the corresponding segment in the physical property segment structure. The process involves several steps: First, obtaining time-corrected segmented physical property parameters. This includes generating a time correction factor reflecting the temporal changes in the segmented physical property parameters based on the changes in the laying state of each segment. This involves: extracting segmented change information characterizing the thermal diffusion, axial stress coupling, and transverse shear coupling components based on the changes in the laying state of each segment; constructing a change factor indicating the temporal magnitude of the segmented physical property parameters based on the segmented change information, and aggregating the change factor according to the segmented position; generating a time correction factor reflecting the temporal changes in the segmented physical property parameters based on the aggregated change factor. Finally, updating the corresponding segmented solution structure in the multiphysics joint calibration model based on the time-corrected segmented physical property parameters yields an updated multiphysics joint calibration model.

[0012] Optionally, based on the updated multiphysics joint calibration model, the segmented physical quantity calculation results are integrated along the line to generate a distribution of physical quantities along the line and output it as a joint calibration result. This includes: determining the spatial positional relationship of each segment based on the updated multiphysics joint calibration model, and arranging the segmented physical quantity calculation results of each segment in order according to the spatial positional relationship; performing boundary continuity construction processing on the arranged segmented physical quantity calculation results to establish physical quantity continuity at the boundary positions of adjacent segments, so that the temperature calculation quantity and the stress calculation quantity form a continuous physical quantity sequence along the line; generating a distribution of physical quantities along the line to characterize the changes in physical quantities along the distributed optical fiber based on the continuous physical quantity sequence, and outputting the distribution of physical quantities along the line as a joint calibration result.

[0013] A second aspect of the present invention provides a multi-physics joint calibration system for distributed optical fibers. The system includes: an initialization unit for acquiring multi-source response quantities and physical property information based on the deployment information along the distributed optical fiber; a solution unit for constructing a physical property segmentation structure containing segmented physical property parameters based on the physical property information, and inputting the multi-source response quantities and the physical property segmentation structure into a multi-physics joint calibration model to generate segmented physical quantity solution results; an update unit for acquiring the laying state change quantity based on the laying state of the distributed optical fiber, and mapping the laying state change quantity to a time correction quantity of the physical property segmentation structure to update the multi-physics joint calibration model; and a calibration unit for performing along-line integration processing on the segmented physical quantity solution results based on the updated multi-physics joint calibration model, generating along-line physical quantity distribution, and outputting it as a joint calibration result.

[0014] A third aspect of the present invention provides an electronic device, comprising: one or more processors; and a storage device having stored one or more programs thereon, wherein when the one or more programs are executed by the one or more processors, the one or more processors implement the multiphysics joint calibration method for distributed optical fibers as described above.

[0015] On the other hand, the present invention provides a computer-readable storage medium storing instructions that, when executed on a computer, cause the computer to perform the above-described multiphysics joint calibration method for distributed optical fibers.

[0016] Through the above technical solution, this invention obtains multi-source response quantities based on the deployment information along the distributed optical fiber, and simultaneously acquires physical property information such as optical fiber material, coating structure, and laying method. This solution can accurately obtain the basic data required to construct the calibration model. By establishing a segmented structure of physical properties, the thermal diffusion capacity, stress coupling characteristics, and lateral transmission conditions of different segments can be independently expressed, so that the calculation of temperature and stress quantities no longer depends on the assumption of consistency of parameters throughout the entire optical fiber. Combined with the segmented solution process of the multi-physics joint calibration model, the corresponding temperature and stress calculation quantities can be obtained according to the characteristics of each segment. Furthermore, by introducing the laying state change quantity and generating the corresponding time correction quantity, the model can maintain its adaptability to changes in optical fiber coupling state during long-term operation. Finally, the segmented physical quantity calculation results obtained from the updated model are integrated along the line to obtain a complete and continuous distribution of physical quantities along the line, supporting stable monitoring in a multi-physics environment.

[0017] Other features and advantages of the embodiments of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0018] The accompanying drawings are provided to further illustrate embodiments of the present invention and form part of the specification. They are used together with the following detailed description to explain the embodiments of the present invention, but do not constitute a limitation thereof. In the drawings: Figure 1 This is a flowchart of the steps of a multi-physics joint calibration method for distributed optical fibers provided by one embodiment of the present invention; Figure 2 This is a system architecture diagram of a multi-physics joint calibration system for distributed optical fibers provided in one embodiment of the present invention; Figure 3 This is an internal structural diagram of a computer device provided in one embodiment of the present invention. Detailed Implementation

[0019] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0020] like Figure 1 As shown, this invention provides a multi-physics joint calibration method for distributed optical fibers, the method comprising: Step S10: Obtain multi-source response quantities and physical property information based on the deployment information along the distributed optical fiber.

[0021] Specifically, based on the deployment information along the distributed optical fiber, Raman response quantities for characterizing temperature response, Brillouin frequency shift response quantities for characterizing temperature and stress mixed response, and Rayleigh scattering response quantities for characterizing stress response are extracted, and the Raman response quantities, Brillouin frequency shift response quantities, and Rayleigh scattering response quantities are used as multi-source response quantities; based on the deployment information along the line, physical property information for characterizing optical fiber material, coating structure, and laying method is extracted.

[0022] In this embodiment of the invention, the deployment information along the distributed optical fiber already provides the spatial location, orientation, and environmental contact conditions, thus serving as the basic coordinate framework for subsequent data organization. Based on this deployment information, the response data and physical property parameters at each sampling location are uniformly numbered and aligned, allowing subsequent calculations to run under the same spatial index, avoiding location mismatches or segment confusion. In this way, multi-source response quantities and physical property information are no longer loose data, but are fixed on a clear along-line coordinate system.

[0023] Regarding the acquisition of multi-source responses, the Raman response primarily derives from the sensitivity of backscattering Raman intensity to temperature variations. During measurement, the ratio of the inverse Stokes and Stokes components at each sampling point along the line is calculated to obtain the temperature-dependent Raman signal amplitude. The Brillouin frequency shift response reflects the shift of the Brillouin scattering spectral center frequency relative to a static reference. This shift is influenced by both the temperature field and the axial stress field, thus it is denoted as a mixed temperature and stress response. The Rayleigh scattering response is typically based on the phase or intensity changes of backscattered Rayleigh scattering. The drift in the scattering pattern caused by small strains is obtained through a line-correlation matching method, used to characterize stress or strain distribution. These three types of responses each have advantages in different physical quantities. Therefore, the Raman, Brillouin frequency shift, and Rayleigh scattering responses are collectively classified as multi-source responses, allowing for joint modeling of different physical sensitivities within the same data structure.

[0024] The deployment information along the fiber optic route acts as an "index table." Each sampling location corresponds to a set of multi-source response quantities: a set of Raman response scalars or vectors, a set of Brillouin frequency shift data, and a set of Rayleigh scattering eigenvalues. All of these data are bound to their physical spatial locations through the deployment information along the route. The advantage of this setup is that the temperature and stress responses of any fiber segment can be simultaneously retrieved under the same location index, avoiding the need to handle coordinate transformation issues during the joint calibration phase. For those skilled in the art, this indexing method based on deployment information along the route is relatively straightforward, and its engineering implementation difficulty is also controllable.

[0025] Obtaining fiber optic property information relies on understanding the fiber structure and laying environment. Deployment information along the route typically includes fiber type markings, sheath material records, and laying process records. For example, one section might use single-mode fiber with polymer coating, externally protected by steel pipe, and installed using a tight-coupled fixing method; another section might use loose tube laying with different external sheathing materials. Classifying fiber materials based on these records allows for differentiation of different core refractive index doping schemes and different coating materials, thus providing a basis for setting subsequent thermal diffusion and mechanical coupling parameters. Coating structure information includes the number of coating layers, material type, and thickness combination; laying method information covers whether it is direct burial, laying in a duct, or attached to the surface of a component, and whether fasteners are used for constraint.

[0026] Step S20: Construct a segmented physical property structure containing segmented physical property parameters based on the physical property information, and input the multi-source response quantity and the segmented physical property structure into a multi-physics joint calibration model to generate segmented physical quantity solution results.

[0027] Specifically, constructing a property segmentation structure containing segmented property parameters based on the aforementioned property information includes: dividing the distributed optical fiber along its route into segments based on the aforementioned property information to obtain property segments corresponding to each segment; extracting thermal diffusion parameters, axial stress coupling parameters, and transverse shear coupling parameters based on the optical fiber material, coating structure, and laying method contained in each property segment, and combining the thermal diffusion parameters, axial stress coupling parameters, and transverse shear coupling parameters to form segmented property parameters; and writing the segmented property parameters into the corresponding property segments to construct a property segmentation structure containing multiple property segments and their corresponding segmented property parameters.

[0028] Furthermore, the multi-source response quantities and the segmented material property structure are input into the multi-physics joint calibration model to generate segmented physical quantity calculation results. This includes: determining the segmented material property parameters corresponding to each segment based on the segmented material property structure, and writing the segmented material property parameters into the segmented calculation structure of the multi-physics joint calibration model; performing position matching on the multi-source response quantities corresponding to each segment based on the input requirements of the segmented calculation structure, and writing the matched multi-source response quantities into the multi-physics joint calibration model; performing a joint solution operation of temperature and stress quantities based on the written segmented material property parameters and the multi-source response quantities to obtain the temperature and stress calculation quantities corresponding to each segment; and writing the temperature and stress calculation quantities into the segmented material property structure according to the segmented position to form segmented physical quantity calculation results.

[0029] Furthermore, based on the written segmented physical property parameters and the multi-source response quantities, a joint solution operation for temperature and stress quantities is performed to obtain the temperature and stress solutions for each segment. This includes: determining the solution coefficients for characterizing temperature-sensitive and stress-sensitive terms based on the segmented physical property parameters, and configuring the solution coefficients and the multi-source response quantities for each segment in a one-to-one correspondence; performing matrix solving based on the configured solution coefficients and multi-source response quantities to separate the temperature-sensitive and stress-sensitive components for each segment, obtaining the temperature solution quantity for characterizing temperature changes and the stress solution quantity for characterizing stress changes; and organizing the temperature and stress solutions according to the segment positions so that the temperature and stress solutions are written into the segmented physical property structure to form segmented physical quantity solution results.

[0030] In this embodiment of the invention, in distributed optical fiber monitoring, the deployment along the line often exhibits significant segmental differences. For example, some locations use tightly coupled laying, while others may be in loose tube or bare fiber environments. These differences directly affect heat diffusion efficiency, axial stress transmission capability, and the number of transverse shear paths. The purpose of segmenting based on physical property information is to give these differences a clear expression space in the model structure, avoiding the mixing of different physical property characteristics into a whole during subsequent solution processes. The segmentation is based primarily on the deployment records along the line, which provide the fiber type, sheath material, and contact state at each location. The segmentation process is not complex, but it has a significant impact on the stability of the actual modeling, because the number of segments, segment length, and the span between the physical property parameters of each segment all affect the subsequent solution convergence conditions. After segmentation, each physical property segment has an independent index used to bind the set of physical property parameters of that segment.

[0031] The physical properties themselves originate from the fiber material, coating structure, and laying method. In a typical section, the core refractive index and dopant type determine the thermal diffusion capability; the coating material and thickness determine the lateral shear coupling characteristics; and the laying method affects the effective transmission path of axial stress. Thermal diffusion parameters are generally used to describe the efficiency of temperature propagation along the core direction and can be inferred from a combination of the material's thermal conductivity, specific heat capacity, and density. Axial stress coupling parameters focus on the consistency of extension between the fiber and the surrounding medium; this parameter is usually higher when tight coupling is significant. Lateral shear coupling parameters depend more on the coating thickness and sheath material, determining the range of the fiber's sensitivity to lateral displacement. The combination of these three physical properties constitutes a segmented set of physical properties used to describe the basic response capability of this section in temperature and stress fields. This combination has a relatively simple structure but covers the most core physical behaviors of optical fibers in practical engineering.

[0032] After the generated segmented physical property parameters are written into the corresponding physical property segments, the entire segmented structure becomes callable. Each segment contains a set of three-dimensional physical property parameter values, corresponding to thermal diffusion, axial stress coupling, and transverse shear coupling, respectively. The advantage of this structure is that it can directly support segmented solution logic without repeatedly extracting parameters from the original physical property information during the solution process. For those skilled in the art, the segmented physical property structure is similar to an indexed physical property field library, which is frequently called in subsequent models, and its data organization method is more conducive to matrix processing.

[0033] When inputting multi-source response quantities and piecewise material property structures into a multiphysics joint calibration model, two alignment steps are required. The first alignment step is location matching, which associates the material property parameters of each segment with the multi-source response quantities at the corresponding locations. The second alignment step is writing the solver units. The model typically contains multiple piecewise solver modules, each responsible for processing an independent segment. Therefore, the piecewise material property parameters need to be written into these solver modules, corresponding to the initialization of the model structure. Input requirements usually include the dimension, unit, and normalization method of each material property parameter. These requirements ensure that the numerical ranges between different segments remain within a reasonable range during the solution process, without burdening the stability of the solution matrix.

[0034] The joint solution process is the core of this section. Due to the different sensitivities of Raman, Brillouin, and Rayleigh, their coupling relationship can be described by a set of linear hybrid equations. To separate temperature and stress variations within each segment, the model constructs a solution matrix corresponding to that segment. For a segment j, it can be written as:

[0035] in: The change in Raman response represents the temperature-sensitive signal in segment j; The Brillouin frequency shift is a mixture of temperature and stress effects; The variation in Rayleigh scattering is mainly manifested in stress-sensitive terms; , , These are the sensitivity coefficients of Raman, Brillouin, and Rayleigh to temperature changes, respectively, derived from the thermal diffusivity in the segmented physical property parameters; , , These are the sensitivity coefficients of the three types of responses to stress changes, and are related to the axial stress coupling parameter and the transverse shear coupling parameter; The temperature calculation for segment j; Let be the stress solution quantity for segment j.

[0036] The solution process typically involves performing inverse or pseudo-inverse operations on the above matrix to obtain the solution in the least squares sense. and The stability of the matrix depends on the condition number between the sensitivity coefficients; therefore, the piecewise structure of physical properties plays a role here because it provides independent sensitivity coefficients for each segment, which helps improve the solvability of the equation system. In practice, the model builds a series of solution matrices based on the segment positions, processes them in batches into vector form, and then maps them to the sequence structure of the multi-source response.

[0037] After the temperature and stress calculations are obtained segment by segment, they need to be organized according to the segment positions so that the two types of physical quantities occupy fixed positions in the property segment structure. This organization process is relatively simple and mainly includes sequential arrangement, type labeling, and segment boundary positioning. The organized data is then written back into the property segment structure to form the segmented physical quantity calculation results, providing input for the subsequent update process based on the laying status.

[0038] Step S30: Obtain the change in the laying status based on the laying status of the distributed optical fiber, and map the change in the laying status to the time correction amount of the physical property segment structure to update the multiphysics joint calibration model.

[0039] Specifically, based on the laying status of distributed optical fibers, laying status information is extracted to characterize the contact form, constraint method, and burial depth conditions. The laying status change of each segment is determined based on this information. A time correction amount is generated based on the laying status change amount to reflect the time variation of the segment's physical property parameters. This time correction amount is then associated with the corresponding segment in the physical property segmentation structure to obtain the time-corrected segment physical property parameters. The corresponding segment solution structure in the multiphysics joint calibration model is updated based on the time-corrected segment physical property parameters to obtain the updated multiphysics joint calibration model.

[0040] Furthermore, generating a time correction amount to reflect the time changes of segmented physical property parameters based on the laying state change amount includes: extracting segmented change information to characterize the thermal diffusion change component, axial stress coupling change component, and transverse shear coupling change component based on the laying state change amount corresponding to each segment; constructing a change factor to indicate the time change amplitude of segmented physical property parameters based on the segmented change information, and aggregating the change factor according to the segment position; and generating a time correction amount to reflect the time changes of segmented physical property parameters based on the aggregated change factor.

[0041] In this embodiment of the invention, optical fibers along the route may experience settlement, loosening, or localized compression during service, which alters the contact between the fiber and the surrounding medium. The purpose of extracting changes based on laying status information is to quantify these external changes. The contact form determines the stress transmission path, the constraint method affects the continuity of axial force, and the burial depth often alters the boundary conditions of the thermal and stress fields. This step identifies whether the laying status has shifted segment by segment based on these factors, forming state change quantities for subsequent numerical processing.

[0042] Laying status information is usually present in a relatively scattered form. For example, construction data may record that one section is protected by a pipe, while another section is directly buried in the concrete layer; monitoring logs may contain descriptions of loosening at a certain location or changes in backfill material. To transform this information into a computable structure, three basic attributes need to be identified: contact type, constraint method, and burial depth. After this identification, the basic state of each segment can be compared with the current state to infer the amount of change in laying status. This change does not need to be particularly complex; as long as it describes the trend or magnitude of the change, it can be used to construct time correction logic later. The main purpose of this step is to introduce external environmental disturbances into the calibration system, enabling the model to align with the actual scenario.

[0043] The construction of the time correction factor is a crucial part of this logic. The state change factor is essentially just an external representation; to make the model parameters change over time, this external representation needs to be projected onto the physical property space. This projection process can be accomplished by extracting the thermal diffusion change component, the axial stress coupling change component, and the transverse shear coupling change component. These three types of change components correspond one-to-one with the piecewise physical property parameters, thus providing a clear direction for correction. Those skilled in the art typically formulate quantitative or semi-quantitative change components based on changes in material thermal conductivity or stress transmission paths, which are then used to construct subsequent change factors.

[0044] The variation factor acts like a weight, telling the model how much the physical property parameters of each segment should deviate from the original parameters at the current time. To express this deviation, the variation component needs to be normalized and encapsulated so that it can exist as an independent numerical term. Variation factors are usually aggregated by segment index, and the aggregated structure is easy to call directly in the model and also easy to match with the physical property segment structure. After this processing, the variation factor has a form that can be written into the physical property parameter structure, and also provides the necessary input for the next step of generating time corrections.

[0045] The generation logic of time corrections does not emphasize complex mathematics, but only the clarity of the data path. Variation factors are often synthesized through simple linear mappings or weighted functions, making them effective quantities describing the magnitude of time-dependent changes in physical property parameters. Time corrections do not need to replace physical property parameters, nor do they need to cover all original values; they only need to describe "how much the original physical property parameters should have deviated under the current installation condition." In engineering practice, such corrections are usually expressed in incremental form, so their association with the segmented structure of physical properties tends to be direct, i.e., the time correction is attached to the physical property segment according to its segment position.

[0046] Once the time correction is correlated with the piecewise material property structure, the piecewise material property parameters acquire new numerical versions, commonly referred to as time-corrected piecewise material property parameters. These corrected parameters are input into the joint calibration model to refresh the model's internal solution structure. The solution structure typically refers to the sensitivity coefficient matrix or numerical solution units organized piecewise within the model, which rely on the stability of the material property parameters for calculation. When the material property parameters change, these solution units also need to be updated synchronously. The update process is often performed piecewise, without involving the overall reconstruction of the model, but it has a direct impact on the solution results and is closer to actual monitoring scenarios.

[0047] To illustrate the relationship between the variation factor and the physical property parameters, a simple mapping formula can be given. For example, the corrected form of the thermal diffusivity parameter for segment j can be written as:

[0048] in, This represents the thermal diffusion parameters at the current moment; These are the initial thermal diffusion parameters; This indicates the thermal diffusivity variation factor for the corresponding section; This represents the change in the laying condition of section j. The other two types of parameters, namely the axial stress coupling parameter and the transverse shear coupling parameter, can also be modified using the same structure, simply by replacing the corresponding variation factors and parameter terms. This formula does not aim to cover all physical processes, but rather provides a reproducible method that enables those skilled in the art to understand how time corrections act in the parameter space.

[0049] Once the parameters for all segments have been corrected, the multiphysics joint calibration model is in a new numerical state. The model update process itself is not complex; it simply requires rewriting the corrected segmental property parameters into the corresponding solution structure. The new solution structure can more accurately reflect the response characteristics of the optical fiber under its current laying condition, making subsequent temperature and stress calculations more realistic.

[0050] Step S40: Based on the updated multiphysics joint calibration model, perform line integration processing on the segmented physical quantity solution results to generate the line physical quantity distribution and output it as the joint calibration result.

[0051] Specifically, the spatial relationship of each segment is determined based on the updated multiphysics joint calibration model, and the solution results of the segmented physical quantities of each segment are arranged in order according to the spatial relationship. Based on the arranged solution results of the segmented physical quantities, the boundary continuity construction process of the physical quantities of adjacent segments is performed to establish the continuity of physical quantities at the boundary positions of adjacent segments, so that the temperature solution and stress solution form a continuous sequence of physical quantities along the line. Based on the continuous sequence of physical quantities, a distribution of physical quantities along the line is generated to characterize the changes of physical quantities along the distributed optical fiber, and the distribution of physical quantities along the line is output as the joint calibration result.

[0052] In this embodiment of the invention, the segmented physical property parameters were previously organized by segment index. Here, these indices need to be remapped back to the physical coordinates along the optical fiber. Specifically, based on the start and end positions of the segments recorded in the updated multiphysics joint calibration model, the calculated results of each segment's physical quantity are mapped one-to-one with the corresponding distance along the fiber. For segments with bends, loops, or different laying depths, path length or projected length can be introduced as a sorting criterion to avoid spatial overlap. After this processing, the segmentation results form an ordered sequence in the data structure, providing a relatively clean foundation for subsequent continuous processing steps.

[0053] After spatial sorting, the transition relationship between segments needs to be considered. The segmented calculation results are often averages or representative values ​​obtained within each segment; direct splicing will create significant abrupt changes at the boundaries. To mitigate this unnatural discontinuity, a transition band can be introduced at the boundary between adjacent segments. The length of the transition band is selected based on the fiber spatial resolution and engineering requirements. Within this region, the temperature and stress calculations of upstream and downstream segments are weighted and mixed. The weights can vary linearly with location or according to a preset curve, but the core purpose is to establish a smooth numerical connection at the boundary. After this treatment, adjacent segments exhibit a more continuous numerical trend, making physical interpretation easier to establish.

[0054] The construction of the continuous physical quantity sequence depends on the results of the first two steps. After position sorting and transition smoothing, each sampling point along the line can obtain a set of temperature and stress calculations to describe the state of that point at the current moment. To maintain clarity in the data structure, a common practice is to discretize the line direction into a one-dimensional grid, with each grid node corresponding to a spatial location, and then write the smoothed segmented values ​​into these nodes. If higher resolution is required in certain sections, a denser sampling interval can be used in those sections, and the interpolation strategy can be adjusted accordingly. The final result is a continuous physical quantity sequence along the line direction, preserving both temperature and stress dimensions.

[0055] Based on a continuous sequence of physical quantities, the distribution of physical quantities along the line can be naturally constructed. For temperature, temperature curves along the line can be plotted or corresponding numerical distribution tables can be generated; for stress, stress profiles or lists of critical sections along the line can be generated. If multi-physics coupling effects need to be considered, temperature and stress information can be combined at each location to provide a comprehensive index. Regardless of the representation method used, the core work revolves around statistical, filtering, or visualization processing of this one-dimensional sequence. The final distribution of physical quantities along the line, as the joint calibration result output, is used for subsequent safety assessments, structural diagnostics, or operational condition optimization, and also provides a unified benchmark for comparative analysis of long-term monitoring data.

[0056] In another possible implementation, in-line integration processing can be applied to special scenarios with periodic mechanical disturbances. For example, some optical fibers are laid near the vibrating base of large equipment, which will generate predictable micro-amplitude reciprocating displacements during its operating cycle. These displacements will leave regular fluctuations in the segmented physical quantity calculation results, causing a slight offset at the boundaries of the conventional linear transition method. To address this, a transition window based on the vibration period can be set between segments. This window is divided into several phase segments according to the equipment's operating cycle, and different weighting strategies are applied in different phases, giving the transition region a certain degree of elasticity in the time dimension. After this processing, the boundary smoothing process not only considers spatial location but also takes into account the repetitive characteristics of the temporal phase.

[0057] When generating a continuous sequence of physical quantities, an adaptive interpolation interval can be used in vibration-sensitive sections. Traditional fixed intervals may fail to capture details in areas with high fluctuation frequencies. The adaptive strategy adjusts the sampling density based on the fluctuation amplitude of the previous moment, ensuring that the distribution of physical quantities along the line maintains higher resolution in the vibration section. The resulting distribution of physical quantities along the line can more accurately reflect the temperature and stress evolution under periodic disturbances in this scenario, providing a more realistic monitoring reference for such components.

[0058] like Figure 2As shown, this invention provides a multi-physics joint calibration system for distributed optical fibers. The system includes: an initialization unit for acquiring multi-source response quantities and physical property information based on the deployment information along the distributed optical fiber; a solution unit for constructing a physical property segmentation structure containing segmented physical property parameters based on the physical property information, and inputting the multi-source response quantities and the physical property segmentation structure into a multi-physics joint calibration model to generate segmented physical quantity solution results; an update unit for acquiring the laying state change quantity based on the laying state of the distributed optical fiber, and mapping the laying state change quantity to the time correction quantity of the physical property segmentation structure to update the multi-physics joint calibration model; and a calibration unit for performing along-line integration processing on the segmented physical quantity solution results based on the updated multi-physics joint calibration model, generating along-line physical quantity distribution, and outputting it as a joint calibration result.

[0059] The present invention also provides a computer-readable storage medium storing instructions that, when executed on a computer, cause the computer to perform the above-described multiphysics joint calibration method for distributed optical fibers.

[0060] This invention also provides an electronic device, including: one or more processors; and a storage device storing one or more programs thereon, wherein when the one or more programs are executed by the one or more processors, the one or more processors implement the multiphysics joint calibration method for distributed optical fibers as described above.

[0061] In one embodiment, a computer device is provided, which may be a server, and its internal structure diagram may be as follows: Figure 3 As shown, the computer device includes a processor A01, a network interface A02, memory (not shown), and a database (not shown) connected via a system bus. The processor A01 provides computational and control capabilities. The memory includes internal memory A03 and a non-volatile storage medium A06. The non-volatile storage medium A06 stores an operating system B01, a computer program B02, and a database (not shown). The internal memory A03 provides an environment for the operation of the operating system B01 and the computer program B02 stored in the non-volatile storage medium A06. The network interface A02 is used for communication with external terminals via a network connection. When the computer program B02 is executed by the processor A01, it implements a multiphysics joint calibration method for distributed optical fibers.

[0062] Those skilled in the art will understand that all or part of the steps in the methods of the above embodiments can be implemented by a program instructing related hardware. This program is stored in a storage medium and includes several instructions to cause a microcontroller, chip, or processor to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as a USB flash drive, a portable hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0063] The optional embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the embodiments of the present invention are not limited to the specific details described above. Within the scope of the technical concept of the embodiments of the present invention, various simple modifications can be made to the technical solutions of the embodiments of the present invention, and these simple modifications all fall within the protection scope of the embodiments of the present invention. It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the embodiments of the present invention will not further describe the various possible combinations.

[0064] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the embodiments of the present invention, they should also be regarded as the content disclosed by the embodiments of the present invention.

Claims

1. A multi-physics joint calibration method for distributed optical fibers, characterized in that, The method includes: Multi-source response and physical property information are obtained based on the deployment information along the distributed optical fiber; Based on the material property information, a material property segmentation structure containing segmented material property parameters is constructed, and the multi-source response quantity and the material property segmentation structure are input into a multi-physics joint calibration model to generate segmented physical quantity solution results; The laying status change is obtained based on the laying status of distributed optical fiber, and the laying status change is mapped to the time correction amount of the physical property segment structure to update the multi-physics joint calibration model. Based on the updated multiphysics joint calibration model, the segmented physical quantity solution results are integrated along the line to generate the physical quantity distribution along the line and output it as the joint calibration result.

2. The multiphysics joint calibration method for distributed optical fibers according to claim 1, characterized in that, Based on the deployment information along the distributed optical fiber, multi-source response and physical property information are obtained, including: Based on the deployment information along the distributed optical fiber, Raman response quantity for characterizing temperature response, Brillouin frequency shift response quantity for characterizing temperature and stress mixed response, and Rayleigh scattering response quantity for characterizing stress response are extracted, and the Raman response quantity, Brillouin frequency shift response quantity and Rayleigh scattering response quantity are used as the multi-source response quantity. Based on the deployment information along the route, physical property information is extracted to characterize the optical fiber material, coating structure, and laying method.

3. The multiphysics joint calibration method for distributed optical fibers according to claim 2, characterized in that, Based on the aforementioned physical property information, a segmented physical property structure containing segmented physical property parameters is constructed, including: Based on the aforementioned physical property information, the distributed optical fiber is segmented along its route to obtain the physical property sections corresponding to each segment. Based on the optical fiber material, coating structure and laying method contained in each physical property segment, thermal diffusion parameters, axial stress coupling parameters and transverse shear coupling parameters are extracted respectively, and the thermal diffusion parameters, axial stress coupling parameters and transverse shear coupling parameters are combined to form segmented physical property parameters; The segmented physical property parameters are written into the corresponding physical property segments to construct a physical property segmentation structure containing multiple physical property segments and their corresponding segmented physical property parameters.

4. The multiphysics joint calibration method for distributed optical fibers according to claim 3, characterized in that, The multi-source response and the piecewise structure of the physical properties are input into a multi-physics joint calibration model to generate piecewise physical quantity solution results, including: Based on the property segmentation structure, the segmented property parameters corresponding to each segment are determined, and the segmented property parameters are written into the segmented solution structure of the multiphysics joint calibration model. Based on the input requirements of the segmented solution structure, position matching is performed on the multi-source response quantities of each corresponding segment, and the matched multi-source response quantities are written into the multi-physics joint calibration model. Based on the written segmented physical property parameters and the multi-source response quantity, perform a joint solution operation for temperature and stress quantities to obtain the temperature and stress solutions for each segment. The calculated temperature and stress values ​​are written into the property segmentation structure according to the segmented positions to form segmented physical quantity calculation results.

5. The multiphysics joint calibration method for distributed optical fibers according to claim 4, characterized in that, Based on the written segmented physical property parameters and the multi-source response quantities, a joint solution operation for temperature and stress quantities is performed to obtain the temperature and stress solutions for each segment, including: Based on the segmented physical property parameters, the solution coefficients used to characterize the temperature-sensitive and stress-sensitive terms are determined, and the solution coefficients are input and configured one-to-one with the multi-source response quantities of each segment. Based on the solution coefficients and multi-source response quantities after completing the input configuration, matrix solving is performed to separate the temperature-sensitive components and stress-sensitive components of each segment, so as to obtain the temperature solution quantity used to characterize the temperature change and the stress solution quantity used to characterize the stress change.

6. The multiphysics joint calibration method for distributed optical fibers according to claim 1, characterized in that, Based on the laying status of distributed optical fibers, the change in laying status is obtained, and the change in laying status is mapped to the time correction amount of the material property segmentation structure to update the multiphysics joint calibration model, including: Based on the distributed optical fiber, the laying status information along the line is extracted to characterize the contact form, constraint method and burial depth conditions, and the laying status change of each segment is determined based on the laying status information. Based on the changes in the laying status, a time correction amount is generated to reflect the time changes in the segmented physical property parameters. This time correction amount is then associated with the corresponding segment in the physical property segmentation structure to obtain the time-corrected segmented physical property parameters. The process of generating a time correction amount to reflect the time changes in segmented physical property parameters based on the changes in the laying state includes: extracting segmented change information to characterize the thermal diffusion change component, the axial stress coupling change component, and the transverse shear coupling change component based on the changes in the laying state of each segment; constructing a change factor to indicate the amplitude of the time changes in segmented physical property parameters based on the segmented change information, and aggregating the change factor according to the segmented position; and generating a time correction amount to reflect the time changes in segmented physical property parameters based on the aggregated change factor. The corresponding piecewise solution structure in the multiphysics joint calibration model is updated based on the time-corrected piecewise physical property parameters to obtain the updated multiphysics joint calibration model.

7. The multiphysics joint calibration method for distributed optical fibers according to claim 1, characterized in that, Based on the updated multiphysics joint calibration model, the segmented physical quantity calculation results are integrated along the line to generate the physical quantity distribution along the line and output as the joint calibration result, including: The spatial positional relationship of each segment is determined based on the updated multiphysics joint calibration model, and the solution results of the segmented physical quantities of each segment are arranged in order according to the spatial positional relationship. Based on the calculated results of the segmented physical quantities after arrangement, the boundary continuity construction process of adjacent segmented physical quantities is performed to establish the continuity of physical quantities at the boundary position of adjacent segments, so that the temperature calculation quantity and the stress calculation quantity form a continuous sequence of physical quantities along the line direction. Based on the continuous sequence of physical quantities, a distribution of physical quantities along the line is generated to characterize the changes in physical quantities along the distributed optical fiber, and the distribution of physical quantities along the line is output as a joint calibration result.

8. A multiphysics joint calibration system for distributed optical fibers, characterized in that, The system includes: The initial unit is used to acquire multi-source response quantities and physical property information based on the deployment information along the distributed optical fiber; The calculation unit is used to construct a segmented physical property structure containing segmented physical property parameters based on the physical property information, and input the multi-source response quantity and the segmented physical property structure into a multi-physics joint calibration model to generate segmented physical quantity calculation results. The update unit is used to obtain the change in the laying status based on the laying status of the distributed optical fiber, and map the change in the laying status to the time correction amount of the physical property segment structure to update the multi-physics joint calibration model. The calibration unit is used to perform line-integration processing on the segmented physical quantity solution results based on the updated multi-physics joint calibration model, generate the line-integrated physical quantity distribution, and output it as the joint calibration result.

9. An electronic device, characterized in that, include: One or more processors; A storage device having stored one or more programs that, when executed by one or more processors, cause the one or more processors to implement the multiphysics joint calibration method for distributed optical fibers as described in any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores instructions that, when executed on a computer, cause the computer to perform the multiphysics joint calibration method for distributed optical fibers as described in any one of claims 1-7.

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