Ship loss factor rapid attenuation section dynamic fitting method and device, electronic equipment and storage medium

Abstract

The invention provides a ship loss factor rapid attenuation section dynamic fitting method and device, electronic equipment and a storage medium, and belongs to the field of ship and ocean engineering testing. The problems that in the loss factor calculation process, the signal-to-noise ratio sensitive characteristic is presented, and the anti-interference capacity of abnormal signals is insufficient are solved. The ship loss factor rapid attenuation section dynamic fitting method comprises the following steps that a to-be-measured structure is restrained, and acceleration sensors are evenly arranged on the surface of the to-be-measured structure; storing time-calendar attenuation signals of the acceleration sensors after the acquired signals are attenuated stably; processing the time calendar attenuation signal to obtain an analysis signal and an envelope thereof; dynamically fitting the loss factor, and identifying a rapid attenuation time period; and obtaining an equivalent structure loss factor, and performing root mean square processing on the multi-region loss factor curve with good consistency to obtain the equivalent structure loss factor. The method is mainly used for dynamic fitting of the rapid attenuation section of the ship loss factor.

Description

Technical Field

[0001] This invention belongs to the field of ship and marine engineering testing, and in particular relates to a method, device, electronic equipment and storage medium for dynamic fitting of the rapid decay segment of ship loss factor. Background Technology

[0002] The ship loss factor is an important structural parameter characterizing the damping properties of a system. It is a crucial input parameter in the analysis and prediction of ship vibration and noise transmission, significantly impacting the dissipation of vibration energy in ship systems. In practical testing, the loss factor is a key parameter for measuring and determining a ship's capabilities, significantly influencing both ship vibration and noise transmission and prediction analysis. Currently, the industry commonly uses methods such as transient attenuation and DMA to test the ship structural loss factor, providing initial accumulation for a ship structural loss factor database and offering system parameter inputs for numerical calculation methods of ship structural noise. Therefore, research on ship loss factor testing methods is of great significance for improving the accuracy and speed of underwater radiated noise prediction analysis for ships.

[0003] However, the traditional transient decay method has significant limitations in practical applications: due to the nonlinear effects in the vibration decay process of ship structures, when traditional methods directly perform linear fitting on the full-time decay curve within a fixed time window, it is difficult to accurately separate the dynamic characteristics of the rapid decay segment and the slow decay segment, resulting in the calculated absolute value of the slope being generally smaller than the expected value. These problems lead to insufficient reliability of existing methods in assessing ship vibration energy dissipation, especially in the high-frequency loss factor, directly affecting the prediction and assessment effectiveness of ship vibration reduction and noise reduction.

[0004] Therefore, if a loss factor calculation method can be proposed that can adapt to the dynamic attenuation characteristics of ship structures and effectively correct slope deviation, it can effectively improve the engineering applicability of ship vibration and noise prediction and control, and also has important academic significance for the field of vibration and noise research. Summary of the Invention

[0005] In view of this, the present invention aims to propose a dynamic fitting method, device, electronic device and storage medium for the rapid attenuation segment of ship loss factor, so as to solve the problems of signal-to-noise ratio sensitivity and insufficient anti-interference ability of abnormal signals in the process of loss factor calculation.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: According to a first aspect of the present invention, a dynamic fitting method for the rapid decay segment of ship loss factor is provided, comprising the following steps: Constrain the structure under test and uniformly arrange acceleration sensors on the surface of the structure under test; Transient excitation is applied to multiple excitation points with significant spatial differences, and the time-history decay signals of each accelerometer are stored after the acquired signals have decayed and stabilized. For the time-history attenuation signal processing, the vibration component of the target frequency band is separated by a Butterworth bandpass filter. The filtered signal is then subjected to a Hilbert transform to obtain an analytical signal and its envelope. The envelope is used to characterize the amplitude change of the vibration component within the target frequency band. The attenuation curve is obtained by logarithmic operation on the envelope. Dynamically fit the loss factor, identify the decay curve based on diverse decay characteristics, and identify the period of rapid decay. The equivalent structural loss factor is obtained by fitting the attenuation curves during the main attenuation periods to extract structural damping, and then calculating the structural loss factor for each region. By comparing the structural loss factors of each region laterally, abnormal data that deviates from the root mean square trend are eliminated. The root mean square comprehensive processing is performed on the loss factor curves of the multi-region with good consistency, and finally the equivalent structural loss factor characterizing the overall structural vibration energy dissipation characteristics is obtained.

[0007] Furthermore, the constraint method of the structure under test is as follows: the constraint is based on the actual boundary conditions, the excitation points with large spatial position differences are the typical position excitation points of the structure under test, and the transient excitation method is to use a metal hammer with a certain hardness and mass to impact.

[0008] Furthermore, the time-history attenuation signal is acquired multiple times at certain intervals.

[0009] Furthermore, the processing method for the time-history attenuation signal is as follows: determine the cutoff frequency within the target frequency band range of the time-history attenuation signal. and upper cutoff frequency Choose the filter order to balance passband flatness and stopband attenuation characteristics, ensuring a steep transition band for the filtered signal. Perform Hilbert transform to generate orthogonal components. Its frequency domain representation is: in, The imaginary unit, for Fourier transform, For symbolic functions, Constructing analytic signals The format is: The analytical signal retains only the positive frequency for instantaneous feature extraction; Calculate the envelope of the analytic signal : .

[0010] Furthermore, when identifying the rapid decay period, if there are many peak points and the slope is stable, typical peak points in the high-energy concentrated area are selected, and the area with a relatively stable slope is quickly located by combining the bisection method; if the slope fluctuates significantly or not enough peak points are found, the area of ​​decay curve is calculated by the Newton-Coates integral formula, and the interval occupying the main area is selected as the rapid decay time domain interval.

[0011] Furthermore, the specific method for identifying the decay time period is as follows: Based on envelope signal Based on the temporal distribution characteristics, trend determination and stability assessment are performed. If the number of peak points in the envelope exceeds the preset threshold, and the rate of change of the slope of adjacent local peak points is lower than the threshold in the continuous time domain interval, it is determined to be a stable decay stage. For the stable decay stage, peak points that meet the conditions are selected according to the energy ratio criterion. If there are many peak points and the slope is relatively stable over a certain period, the least squares method is used to fit the decay curve of the selected high-energy peak point set to obtain the initial slope of the curve. If the relative deviation between the calculated initial slope value and the expected theoretical value exceeds the allowable range, the time domain interval is subdivided based on the bisection method. For the time domain interval corresponding to the original high-energy region, the peak points of the first part of the time domain interval are extracted for secondary fitting to update the curve slope, i.e., the structural damping. The results are compared with the expected results again, and the iteration is repeated until the relative deviation of the damping estimate is less than the required value, and the final effective attenuation range is recorded. If the curve fluctuates significantly or the number of effective peak points is insufficient, the energy area under the decay curve can be calculated using the Newton-Cotes numerical integration formula: in, , These are the start and end time points of the decay curve's time-domain interval. To calibrate the main decay time domain interval based on nonparametric saliency energy constraints.

[0012] Furthermore, the equivalent structural loss factor is calculated using the following formula: in, The center frequency of the structure, For structural damping, The average loss factor within the frequency band of the structure under test.

[0013] According to a second aspect of the present invention, a dynamic fitting device for the rapid decay segment of a ship loss factor is provided, comprising: The time-history decay signal acquisition module is used to perform transient excitation on multiple excitation points with large spatial differences and store the time-history decay signals of each accelerometer after the acquired signals have decayed and stabilized. The time-history attenuation signal processing module is used to process the time-history attenuation signal. It separates the vibration component of the target frequency band through a Butterworth bandpass filter, performs a Hilbert transform on the filtered signal to obtain the analytical signal and its envelope. The envelope is used to characterize the amplitude change of the vibration component in the target frequency band. The attenuation curve is obtained by logarithmic operation on the envelope. The rapid decay period identification module is used to dynamically fit the loss factor, identify the decay curve based on diverse decay characteristics, and identify the rapid decay period. The equivalent structural loss factor acquisition module is used to acquire the equivalent structural loss factor. It extracts structural damping based on the attenuation curve fitting during the main attenuation period, and then obtains the structural loss factor of each region. By comparing the structural loss factors of each region laterally, abnormal data that deviates from the root mean square trend are eliminated. The root mean square comprehensive processing is performed on the loss factor curves of the multi-region with good consistency, and finally the equivalent structural loss factor characterizing the vibration energy dissipation characteristics of the overall structure is obtained.

[0014] According to a third aspect of the present invention, an electronic device is provided, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the dynamic fitting method for the rapid attenuation segment of ship loss factor as described in the above embodiments.

[0015] According to a fourth aspect of the present invention, a computer-readable storage medium is provided, the computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described method for dynamic fitting of the rapid decay segment of ship loss factor.

[0016] Compared with the prior art, the beneficial effects of the present invention are: This method significantly improves the accuracy and robustness of ship structure loss factor calculation by constructing a dual technical mechanism of diversified attenuation feature identification and iterative optimization. On the one hand, it addresses the technical shortcomings of traditional methods that rely on "linear fitting of attenuation curves across the entire time domain within a fixed time window." This method cannot accurately separate the dynamic characteristics of the rapid attenuation segment from the slow attenuation segment, easily leading to the problem that the absolute value of the fitting slope is generally smaller than the theoretical expected value and the calculation deviation of the loss factor is large. On the other hand, this method, through dynamic identification of attenuation features and iterative optimization, can accurately lock the effective range of rapid attenuation and avoid the interference of the slow attenuation segment on the fitting results. This makes the calculated structural damping and loss factor closer to the true value, effectively solving the core technical pain points of traditional methods, such as difficulty in separating dynamic characteristics and large deviations in calculation results. This provides a more reliable quantitative basis for the assessment of ship structure vibration energy dissipation characteristics. Attached Figure Description

[0017] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is a schematic diagram of a typical ship structure test according to the present invention; Figure 2 This is a flowchart of a dynamic fitting method for the rapid decay segment of ship loss factor as described in this invention; Figure 3 This is a structural block diagram of the dynamic fitting device for the rapid attenuation segment of the ship loss factor according to the present invention. Figure 4 This is a structural block diagram of the electronic device described in this invention. Detailed Implementation

[0018] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0019] The following description, with reference to the accompanying drawings, illustrates a method, apparatus, electronic device, and storage medium for dynamically fitting the rapid attenuation segment of a ship's loss factor according to embodiments of the present invention. Addressing the issues of signal-to-noise ratio sensitivity and insufficient anti-interference capability against abnormal signals mentioned in the background art, the present invention provides a method for dynamically fitting the rapid attenuation segment of a ship's loss factor. This method significantly improves the accuracy and robustness of ship structural loss factor calculation by constructing a dual technical mechanism of diversified attenuation feature identification and iterative optimization. Thus, it solves the problems of signal-to-noise ratio sensitivity and insufficient anti-interference capability against abnormal signals exhibited in the loss factor calculation process.

[0020] Specifically, Figure 1 This is a flowchart illustrating a dynamic fitting method for the rapid decay segment of ship loss factor provided in an embodiment of the present invention.

[0021] like Figure 1 and Figure 2 As shown, the dynamic fitting method for the rapid decay segment of the ship loss factor includes the following steps: In step S101, the structure under test is constrained in a manner that conforms to the actual boundary conditions, and acceleration sensors are uniformly distributed on the surface of the structure under test according to the field test conditions. Figure 1 The diagram shows the specific arrangement of the accelerometer sensors and the direction of signal transmission. The structure under test is constrained by using elastic ropes for hoisting. The arrangement can be made reasonably according to the actual situation.

[0022] In step S102, multiple excitation points with significant spatial differences are set, and transient excitation is performed sequentially using the hammer impact method. After the acquired signal decays and stabilizes, the time-domain decay signals of each sensor are stored. It is recommended to sample multiple times with a long interval. Excitation points should avoid structural locations that are prone to modal nodes, such as choosing a location 1 / 3 of the plate length from the edge. Measurement points should be distributed in a grid pattern, with a spacing of less than one-sixth of the shortest target wavelength. To obtain a wide-spectrum excitation response, a hard hammer head with suitable mass should be used. Operators must be professionally trained to implement vertical, rapid, and transient impact excitation. The rebound characteristics of the hammer head after impact should be utilized to promptly withdraw the hammer head and prevent secondary impacts from interfering with the time-domain results.

[0023] In step S103, the collected data undergoes preliminary processing. The vibration components of the target frequency band are separated using a Butterworth bandpass filter. A Hilbert transform is then performed on the filtered signal to obtain the analytic signal and its envelope, which characterizes the amplitude variation of the vibration components within the target frequency band. The envelope is logarithmically calculated to obtain the attenuation curve. Specifically, the processing method for the time-history attenuation signal is as follows: the cutoff frequency of the time-history attenuation signal within the target frequency band range is determined. and upper cutoff frequency Choose the filter order to balance passband flatness and stopband attenuation characteristics, ensuring a steep transition band for the filtered signal. Perform Hilbert transform to generate orthogonal components. Its frequency domain representation is: in, The imaginary unit, for Fourier transform, For symbolic functions, Constructing analytic signals The format is: The analytical signal retains only the positive frequency for instantaneous feature extraction; Calculate the envelope of the analytic signal : .

[0024] In step S104, the loss factor is dynamically fitted, and the rapid decay time period is identified based on the identification of diverse decay characteristics. If there are many peak points and the slope is stable, typical peak points in the high energy concentration area are selected, and the area with a relatively stable slope is quickly located by combining the bisection method. If the slope fluctuates significantly or not enough peak points are found, the area of ​​decay curve is calculated by the Newton-Coates integral formula, and the interval occupying the main area is selected as the rapid decay time domain interval. Specifically, firstly based on the envelope signal The temporal distribution characteristics are analyzed to determine trends and assess stability. If the number of peak points in the envelope exceeds a preset threshold (e.g., N≥10), and the rate of change of the slope of adjacent local peak points is lower than the threshold (e.g., ≤10%) within a continuous time interval, it is determined to be a stable decay stage. For the stable decay stage, peak points that meet the conditions are selected according to the energy proportion criterion (e.g., with a 25% energy proportion as a reference, the set of discrete peak points on the envelope that satisfy the condition that the peak points are greater than 75% of the global maximum value of the envelope signal is selected).

[0025] If there are many peak points and the slope is relatively stable over a certain period, the least squares method is used to fit the decay curve of the selected high-energy peak point set to obtain the initial slope of the curve. If the relative deviation between the calculated initial slope value and the expected theoretical value exceeds the allowable range (e.g., >100%), the time domain interval is subdivided based on the bisection method. For the time domain interval corresponding to the original high-energy region, the peak points of the first part of the time domain interval are extracted for secondary fitting to update the curve slope, i.e., the structural damping. The results are then compared with the expected results, and the iteration is repeated until the relative deviation of the damping estimate is less than the required value, and the final effective attenuation range is recorded.

[0026] If the curve fluctuates significantly or the number of effective peak points is insufficient, the energy area under the decay curve can be calculated using the Newton-Cotes numerical integration formula: in, , These are the start and end time points of the decay curve's time-domain interval. To calibrate the main decay time domain interval based on nonparametric saliency energy constraints.

[0027] In step S105, structural damping is extracted based on the attenuation curve fitting during the main attenuation period, and then the structural loss factor for each region is obtained. By comparing the loss factors obtained from multiple rapid attenuation segments dynamically, outliers deviating from the root mean square trend are removed. Root mean square comprehensive processing is then applied to the consistent multi-regional loss factor curves to finally obtain the equivalent structural loss factor characterizing the overall structural vibration energy dissipation characteristics. The equivalent structural loss factor is calculated using the following formula: in, The center frequency of the structure, For structural damping, The average loss factor within the frequency band of the structure under test.

[0028] Next, refer to the appendix. Figure 3 A dynamic fitting device for the rapid decay segment of ship loss factor is described according to an embodiment of the present invention.

[0029] Figure 3 This is a block diagram of the dynamic fitting device for the rapid attenuation segment of the ship loss factor according to an embodiment of the present invention.

[0030] like Figure 3 As shown, the dynamic fitting device for the rapid decay segment of the ship loss factor includes: The time-history decay signal acquisition module is used to perform transient excitation on multiple excitation points with large spatial differences and store the time-history decay signals of each accelerometer after the acquired signals have decayed and stabilized. The time-history attenuation signal processing module is used to process the time-history attenuation signal. It separates the vibration component of the target frequency band through a Butterworth bandpass filter, performs a Hilbert transform on the filtered signal to obtain the analytical signal and its envelope. The envelope is used to characterize the amplitude change of the vibration component in the target frequency band. The attenuation curve is obtained by logarithmic operation on the envelope. The rapid decay period identification module is used to dynamically fit the loss factor, identify the decay curve based on diverse decay characteristics, and identify the rapid decay period. The equivalent structural loss factor acquisition module is used to acquire the equivalent structural loss factor. It extracts structural damping based on the attenuation curve fitting during the main attenuation period, and then obtains the structural loss factor of each region. By comparing the structural loss factors of each region laterally, abnormal data that deviates from the root mean square trend are eliminated. The root mean square comprehensive processing is performed on the loss factor curves of the multi-region with good consistency, and finally the equivalent structural loss factor characterizing the vibration energy dissipation characteristics of the overall structure is obtained.

[0031] It should be noted that the explanation of the above-mentioned embodiment of the dynamic fitting method for the rapid decay segment of ship loss factor also applies to the dynamic fitting device for the rapid decay segment of ship loss factor in this embodiment, and will not be repeated here.

[0032] Figure 4 This is a schematic diagram of an electronic device provided in an embodiment of the present invention. The electronic device may include: The memory 401, the processor 402, and the computer program stored on the memory 401 and capable of running on the processor 402.

[0033] When the processor 402 executes the program, it implements the dynamic fitting method for the rapid decay segment of the ship loss factor provided in the above embodiments.

[0034] Furthermore, electronic devices also include: Communication interface 403 is used for communication between memory 401 and processor 402.

[0035] The memory 401 is used to store computer programs that can run on the processor 402.

[0036] Memory 401 may include high-speed RAM memory, and may also include non-volatile memory, such as at least one disk storage device.

[0037] If the memory 401, processor 402, and communication interface 403 are implemented independently, then the communication interface 403, memory 401, and processor 402 can be interconnected via a bus to complete communication between them. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. Buses can be categorized as address buses, data buses, control buses, etc. For ease of representation, Figure 4 The bus is represented by a single thick line, but this does not mean that there is only one bus or one type of bus.

[0038] Optionally, in a specific implementation, if the memory 401, processor 402, and communication interface 403 are integrated on a single chip, then the memory 401, processor 402, and communication interface 403 can communicate with each other through an internal interface.

[0039] Processor 402 may be a central processing unit (CPU), an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement embodiments of the present invention.

[0040] This invention also provides a computer program product, which, when executed by a processor, implements the above-mentioned method for dynamic fitting of the rapid decay segment of ship loss factor.

[0041] This invention also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described method for dynamic fitting of the rapid decay segment of ship loss factors.

[0042] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0043] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "N" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0044] Any process or method description in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or N executable instructions for implementing custom logic functions or processes, and the scope of preferred embodiments of the invention includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as will be understood by those skilled in the art to which embodiments of the invention pertain.

[0045] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0046] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, the N steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. If implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0047] Those skilled in the art will understand that all or part of the steps of the methods described in the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, it includes one or a combination of the steps of the method embodiments.

[0048] Furthermore, the functional units in the various embodiments of the present invention can be integrated into a processing module, or each unit can exist physically separately, or two or more units can be integrated into a module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

[0049] The storage medium mentioned above can be a read-only memory, a disk, or an optical disk, etc. Although embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A method for dynamic fitting of the fast decay segment of a ship loss factor, characterized by, Includes the following steps: Constrain the structure under test and uniformly arrange acceleration sensors on the surface of the structure under test; Transient excitation is applied to multiple excitation points with significant spatial differences, and the time-history decay signals of each accelerometer are stored after the acquired signals have decayed and stabilized. For the time-history attenuation signal processing, the vibration component of the target frequency band is separated by a Butterworth bandpass filter. The filtered signal is then subjected to a Hilbert transform to obtain an analytical signal and its envelope. The envelope is used to characterize the amplitude change of the vibration component within the target frequency band. The attenuation curve is obtained by logarithmic operation on the envelope. Dynamically fit the loss factor, identify the decay curve based on diverse decay characteristics, and identify the period of rapid decay. The equivalent structural loss factor is obtained by fitting the attenuation curves during the main attenuation periods to extract structural damping, and then calculating the structural loss factor for each region. By comparing the structural loss factors of each region laterally, abnormal data that deviates from the root mean square trend are eliminated. The root mean square comprehensive processing is performed on the loss factor curves of the multi-region with good consistency, and finally the equivalent structural loss factor characterizing the overall structural vibration energy dissipation characteristics is obtained.

2. The method for dynamic fitting of the rapid decay segment of ship loss factor according to claim 1, characterized in that, The constraint method of the structure under test is as follows: the constraint is based on the actual boundary conditions. The excitation points with large spatial differences are the typical excitation points of the structure under test. The transient excitation method is to use a metal hammer with a certain hardness and mass to impact.

3. The method for dynamic fitting of the rapid decay segment of ship loss factor according to claim 1, characterized in that: The time-history attenuation signal is acquired multiple times at regular intervals.

4. The method for dynamic fitting of the rapid decay segment of ship loss factor according to claim 1, characterized in that, The processing method for the time-history attenuation signal is as follows: determine the cutoff frequency within the target frequency band range of the time-history attenuation signal. and upper cutoff frequency Choose the filter order to balance passband flatness and stopband attenuation characteristics, ensuring a steep transition band for the filtered signal. Perform Hilbert transform to generate orthogonal components. Its frequency domain representation is: in, The imaginary unit, for Fourier transform, For symbolic functions, Constructing analytic signals The format is: The analytical signal retains only the positive frequency for instantaneous feature extraction; Calculate the envelope of the analytic signal : 。 5. The method for dynamic fitting of the rapid decay segment of ship loss factor according to claim 1, characterized in that: When identifying rapid decay time periods, if there are many peak points and the slope is stable, typical peak points in the high-energy concentrated area are selected, and the dichotomy method is used to quickly locate the area with a relatively stable slope. If the slope fluctuates significantly or a sufficient number of peak points are not found, the area of ​​the decay curve is calculated using the Newton-Coates integral formula, and the interval occupying the main area is selected as the fast decay time domain interval.

6. The method for dynamic fitting of the rapid decay segment of ship loss factor according to claim 5, characterized in that: The specific method for identifying the decay time period is as follows: Based on envelope signal Based on the temporal distribution characteristics, trend determination and stability assessment are performed. If the number of peak points in the envelope exceeds the preset threshold, and the rate of change of the slope of adjacent local peak points is lower than the threshold in the continuous time domain interval, it is determined to be a stable decay stage. For the stable decay phase, the peak point that meets the conditions is selected according to the energy ratio criterion; If there are many peak points and the slope is relatively stable over a certain period, the least squares method is used to fit the decay curve of the selected high-energy peak point set to obtain the initial slope of the curve. If the relative deviation between the calculated initial slope value and the expected theoretical value exceeds the allowable range, the time domain interval is subdivided based on the bisection method. For the time domain interval corresponding to the original high-energy region, the peak points of the first part of the time domain interval are extracted for secondary fitting to update the curve slope, i.e., the structural damping. The results are compared with the expected results again, and the iteration is repeated until the relative deviation of the damping estimate is less than the required value, and the final effective attenuation range is recorded. If the curve fluctuates significantly or the number of effective peak points is insufficient, the energy area under the decay curve can be calculated using the Newton-Cotes numerical integration formula: in, , These are the start and end time points of the decay curve's time-domain interval. To calibrate the main decay time domain interval based on nonparametric saliency energy constraints.

7. The method for dynamic fitting of the rapid decay segment of ship loss factor according to claim 1, characterized in that: The equivalent structural loss factor is calculated using the following formula: in, The center frequency of the structure, For structural damping, The average loss factor within the frequency band of the structure under test.

8. A dynamic fitting device for the rapid decay segment of ship loss factor, characterized in that, include: The time-history decay signal acquisition module is used to perform transient excitation on multiple excitation points with large spatial differences and store the time-history decay signals of each accelerometer after the acquired signals have decayed and stabilized. The time-history attenuation signal processing module is used to process the time-history attenuation signal. It separates the vibration component of the target frequency band through a Butterworth bandpass filter, performs a Hilbert transform on the filtered signal to obtain the analytical signal and its envelope. The envelope is used to characterize the amplitude change of the vibration component in the target frequency band. The attenuation curve is obtained by logarithmic operation on the envelope. The rapid decay period identification module is used to dynamically fit the loss factor, identify the decay curve based on diverse decay characteristics, and identify the rapid decay period. The equivalent structural loss factor acquisition module is used to acquire the equivalent structural loss factor. It extracts structural damping based on the attenuation curve fitting during the main attenuation period, and then obtains the structural loss factor of each region. By comparing the structural loss factors of each region laterally, abnormal data that deviates from the root mean square trend are eliminated. The root mean square comprehensive processing is performed on the loss factor curves of the multi-region with good consistency, and finally the equivalent structural loss factor characterizing the vibration energy dissipation characteristics of the overall structure is obtained.

9. An electronic device, characterized in that, include: A memory, a processor, and a computer program stored in the memory and executable on the processor, the processor executing the program to implement the method as claimed in claims 1-7.

10. A computer-readable storage medium, characterized in that, It stores a computer program thereon, the computer program being used to cause the computer to perform the method as described in claims 1-7.

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