Marine mechanical vibration source OTPA method for eliminating inter-source coupling and discomfort problems

Abstract

The invention discloses a marine mechanical vibration source OTPA method for eliminating the problem of inter-source coupling and discomfort, and the method comprises the steps: determining a target of the transmission path analysis of a working condition of mechanical equipment, and selecting m vibration source measurement points and n target measurement points of at least one piece of mechanical equipment; constructing an independent vibration source measuring point matrix and a mixed vibration source signal matrix, and solving a transfer function matrix; and solving a transmissibility matrix Tm * n by using a truncated total least square regularization algorithm in combination with the vibration source measurement point mixed vibration signal matrix, the target measurement point matrix and the transfer function matrix measured under the d working conditions. According to the method, on the basis of multi-vibration-source signal convolution aliasing characteristics, a cross transfer function among a plurality of coupled vibration sources can be obtained by means of modes with extremely high operability, such as starting of single equipment in a ship or auxiliary manual excitation, and vibration source signals for eliminating coupling among the sources can be calculated in combination with actually measured vibration response of any working condition.

Description

Technical Field

[0001] The present invention belongs to the technical field of mechanical equipment vibration source identification and control in complex environments, and particularly relates to an OTPA method for ship mechanical vibration sources that eliminates inter-source coupling and ill-posed problems. Background Art

[0002] Ships have numerous and widely distributed vibration sources within their machinery. Traditional methods for identifying mechanical noise sources and their propagation pathways often prove unsatisfactory in complex real-world environments and are unable to accurately identify and control them, significantly limiting the ship's operational efficiency and stealth capabilities. The Operational Transfer Path Analysis (OTPA) method has been widely used in the field of mechanical vibration source identification and control due to its advantages, including the ability to accurately reflect the equipment's true operating state, without requiring disassembly of the equipment. However, multiple mechanical vibration sources often cross-couple within a ship. In this situation, signals measured at the source measurement points cannot accurately identify the true mechanical vibration source, and may even detect spurious vibration source signals at non-operating equipment, rendering the OTPA method ineffective. Furthermore, the complex ship environment is subject to significant measurement noise contamination, which can lead to ill-posedness during the OTPA inversion calculation process, easily amplifying calculation errors and causing distortion in the OTPA method's application. Therefore, there is an urgent need to overcome the challenges of the traditional OTPA method, which cannot address the cross-coupling and ill-posedness of vibration sources induced by the complex ship environment, and accurately identify mechanical vibration sources and their propagation pathways. Summary of the Invention

[0003] In view of the shortcomings of the prior art, the present invention provides an OTPA method for ship mechanical vibration sources, which eliminates the problems of inter-source coupling and ill-posedness.

[0004] To achieve the above objectives, the present invention provides an OTPA method for ship machinery vibration sources that eliminates inter-source coupling and ill-posed problems. The method is specifically as follows: 1) Determine the target of mechanical equipment working condition transfer path analysis, select at least one mechanical equipment m Vibration source measurement points and n target measuring points; When the mechanical equipment is turned on individually, s i ( t ) indicates the i ( i =1, 2, ... m ) vibration source measurement point signals when the mechanical equipment is operating independently; When the mechanical equipment is turned on at the same time, c i ( t ) indicates thei ( i =1, 2, ... m ) mixed vibration signals of the vibration source measurement points; 2) Constructing a matrix of independent vibration source measurement points and mixed source signal matrix , solve the transfer function matrix ; 3) Combination d Mixed vibration signal matrix of vibration source measurement points measured under different working conditions , target measurement point matrix and the transfer function matrix , using the truncated total least squares (TTLS) regularization algorithm to solve the transmissibility matrix T m×n ; 4) Then, based on the mixed signal of the vibration source measurement point of the mechanical equipment measured under any working condition , find the target measurement point response value of the corresponding working condition , thereby realizing the vibration contribution analysis, vibration source identification and sound field prediction of each vibration source measurement point to the target measurement point.

[0005] Furthermore, in the step 1), , For the From the vibration source measuring point to the The response function of the propagation path between the vibration source measurement points is: represents the time point of the input signal history, Expressed as The vibration source measurement point signal at the time point, N Indicates the number of time points; And the mixed vibration signal c i ( t ) is converted to frequency domain and expressed as , represents the frequency, where For the From the vibration source measuring point to the The frequency response function between the vibration source measurement points is: Indicates the frequency domain value of the vibration source measurement point.

[0006] Furthermore, in step 2), the independent vibration source measurement point matrix is ​​constructed and mixed source signal matrix , solve the transfer function matrix The process is: When any mechanical equipment is turned on individually, it is recorded as one working condition, and the following conditions are turned on in sequence: r Mechanical equipment is recorded as r Working conditions,r Greater than or equal to m , and according to the equation , expressed as a matrix r The mixed vibration source signal matrix is ​​obtained by combining the mixed vibration source signal of each working condition and the vibration source measurement point signal , independent vibration source measurement point matrix , and satisfies ; Independent vibration source measurement point matrix Chinese elements For the a Working condition, j Independent vibration source measurement point signals, satisfying j ≠ a hour , a =1, 2, ... r ; Mixed source signal matrix Chinese elements For the a Working condition, i Mixed vibration signals of vibration source measuring points; is the transfer function matrix, where the elements are ; Solving the transfer function matrix .

[0007] Furthermore, the specific process of step 3) is as follows: When mechanical equipment is running at the same time, select d Different operating conditions, d Greater than or equal to m , through the transmission rate matrix T m×n , establish the vibration source measurement point matrix Target measurement point matrix The relationship between the two is established to establish the OTPA basic equation to remove the coupling between sources. ; Vibration source measurement point matrix Each column is the response value of all independent vibration source measurement points corresponding to the same working condition, and each row represents a working condition; the target measurement point matrix Each column in is the response value of all target measurement points corresponding to the same working condition, and each row represents a working condition; Since the vibration source measurement point matrix Cannot be obtained directly, by transferring the function matrix , combined with the mixed vibration signal matrix of the vibration source measurement point ,get ; To eliminate the vibration source signal matrix measured under any working conditions and target point signal matrix There are also measurement errors induced Tm×n The inverse of the ill-posed problem is solved by using the truncated total least squares (TTLS) regularization algorithm to solve the transmissibility matrix T m×n .

[0008] Furthermore, the truncated total least squares (TTLS) regularization algorithm is used to solve the transmissibility matrix T m×n The specific steps are as follows: 31) According to Equation, for l The target measuring point is n = l ( l =1,2,……, n ), build the augmented matrix , and perform singular value decomposition into: In the formula, the superscript “ H " represents the matrix conjugate transpose, the matrix Each column vector in ( i =1,2,……, m ) orthogonal, matrix Each column vector in ( j =1,2,……, n +1) Orthogonal, diagonal matrix The diagonal elements of ; 32) The matrix Split into sub-matrices in k is the truncation parameter, represents a complex field; 33) The truncation parameter is k When , the TTLS regularized solution ; 34) Combine the generalized cross-validation criterion and the AIC information criterion to establish the equation , calculate the cutoff parameter k， The filter factor correction coefficient , express of elements; 35) Calculate the truncation parameter k Then, bring it into step 33) to find the corresponding l TTLS regularization solution for target measurement points ; 36) Repeat steps 31) to 35) to find the transmissibility matrix corresponding to all n target measurement points. .

[0009] Furthermore, in step 2), when there is a mechanical device that cannot be turned on independently, excitation is applied to the vibration source measurement point on the mechanical device that cannot be turned on by artificial excitation (such as a hammer, a vibration exciter, etc.).

[0010] Find out from this T m×n The transmissibility matrix eliminates the ill-posedness problem caused by the observation error between the vibration source and the target measuring point, and then the mixed signal of the vibration source measuring point of the mechanical equipment measured under any working condition can be obtained. , the target measurement point response value of the corresponding working condition can be obtained , and then the vibration contribution analysis, vibration source identification and sound field prediction of each vibration source measurement point to the target measurement point can be realized.

[0011] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention is based on the convolution and aliasing characteristics of multi-vibration source signals. With the help of highly operable methods such as starting a single device in the ship or assisting artificial excitation, the cross-transfer function between multiple coupled vibration sources can be obtained. Combined with the measured vibration response of any working condition, the vibration source signal with the coupling between sources removed can be calculated.

[0012] 2. The transmissibility matrix in the OTPA method is solved based on the truncated total least squares method. This method can not only handle ill-posed problems such as solution distortion caused by measurement errors at both the source and target measurement points in a complex ship environment, but also reduce the influence of the cross-coupling characteristics between the vibration sources.

[0013] 3. By applying the OTPA method for ship mechanical vibration sources to eliminate inter-source coupling and ill-posed problems, the vibration source identification and acoustic field radiation noise prediction of multiple coupled mechanical equipment on the ship were realized. The location and contribution analysis of mechanical vibration noise sources were also completed, providing direct support for the precise control of ship vibration sources and their transmission paths. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a 1 / 3 octave comparison chart of the spectrum from each vibration source path point to the 1# measurement point in the embodiment; Figure 2 : This is the contribution vector diagram of the device to the 1# target point at the frequency point in the embodiment; Figure 3 This is a graph showing the contribution of the device to the 1# target point at the peak frequency point in the embodiment. DETAILED DESCRIPTION

[0015] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0016] The present invention provides a ship machinery vibration source OTPA method for eliminating inter-source coupling and ill-posed problems. The method is specifically as follows: 1) Determine the target of mechanical equipment working condition transfer path analysis, select at least one mechanical equipment m Vibration source measurement points and n target measuring points; When the mechanical equipment is turned on individually, s i ( t ) indicates the i ( i =1, 2, ... m ) vibration source measurement point signals when the mechanical equipment is operating independently; When the mechanical equipment is turned on at the same time, c i ( t ) indicates the i ( i =1, 2, ... m ) mixed vibration signals of the vibration source measurement points; , For the From the vibration source measuring point to the The response function of the propagation path between the vibration source measurement points is: represents the time point of the input signal history, Expressed as The vibration source measurement point signal at the time point, N Indicates the number of time points; And the mixed vibration signal c i ( t ) is converted to frequency domain and expressed as , represents the frequency, where For the From the vibration source measuring point to the The frequency response function between the vibration source measurement points is: Indicates the frequency domain value of the vibration source measurement point.

[0017] 2) Constructing a matrix of independent vibration source measurement points and mixed source signal matrix , solve the transfer function matrix ; When any mechanical equipment is turned on individually, it is recorded as one working condition, and the following conditions are turned on in sequence: r Mechanical equipment is recorded as r Working conditions, r Greater than or equal to m , and according to the equation , expressed as a matrix r The mixed vibration source signal matrix is ​​obtained by combining the mixed vibration source signal of each working condition and the vibration source measurement point signal , independent vibration source measurement point matrix , and satisfies ; Independent vibration source measurement point matrix Chinese elements For the a Working condition, j Independent vibration source measurement point signals, satisfying j ≠ a hour , a =1, 2, ... r ; Mixed source signal matrix Chinese elements For the a Working condition, i Mixed vibration signals of vibration source measuring points; is the transfer function matrix, where the elements are ; Solving the transfer function matrix .

[0018] When there is mechanical equipment that cannot be turned on independently, excitation is applied to the vibration source measuring point on the mechanical equipment that cannot be turned on by artificial excitation (such as force hammer, exciter, etc.).

[0019] 3) Combination d Mixed vibration signal matrix of vibration source measurement points measured under different working conditions , target measurement point matrix and the transfer function matrix , using the truncated total least squares (TTLS) regularization algorithm to solve the transmissibility matrix T m×n The specific process is as follows: When mechanical equipment is running at the same time, select d Different operating conditions, d Greater than or equal to m , through the transmission rate matrix T m×n , establish the vibration source measurement point matrix Target measurement point matrix The relationship between the two is established to establish the OTPA basic equation to remove the coupling between sources. ; Vibration source measurement point matrix Each column is the response value of all independent vibration source measurement points corresponding to the same working condition, and each row represents a working condition; the target measurement point matrix Each column in is the response value of all target measurement points corresponding to the same working condition, and each row represents a working condition; Since the vibration source measurement point matrix Cannot be obtained directly, by transferring the function matrix , combined with the mixed vibration signal matrix of the vibration source measurement point ,get ; To eliminate the vibration source signal matrix measured under any working conditions and target point signal matrix There are also measurement errors induced T m×n The inverse of the ill-posed problem is solved by using the truncated total least squares (TTLS) regularization algorithm to solve the transmissibility matrix T m×n , the specific steps are as follows: 31) According to Equation, for l The target measuring point is n = l ( l =1,2,……, n ), build the augmented matrix , and perform singular value decomposition into: In the formula, the superscript “ H " represents the matrix conjugate transpose, the matrix Each column vector in ( i =1,2,……, m ) orthogonal, matrix Each column vector in ( j =1,2,……, n +1) Orthogonal, diagonal matrix The diagonal elements of ; 32) The matrix Split into sub-matrices in k is the truncation parameter, represents a complex field; 33) The truncation parameter is k When , the TTLS regularized solution ; 34) Combine the generalized cross-validation criterion and the AIC information criterion to establish the equation , calculate the cutoff parameter k， The filter factor correction coefficient , express of elements; 35) Calculate the truncation parameter k Then, bring it into step 33) to find the corresponding l TTLS regularization solution for target measurement points ; 36) Repeat steps 31) to 35) to find the transmissibility matrix corresponding to all n target measurement points. .

[0020] 4) From this, we can find T m×n The transmissibility matrix eliminates the ill-posedness problem caused by the observation error between the vibration source and the target measuring point, and then the mixed signal of the vibration source measuring point of the mechanical equipment measured under any working condition can be obtained. , the target measurement point response value of the corresponding working condition can be obtained , and then the vibration contribution analysis, vibration source identification and sound field prediction of each vibration source measurement point to the target measurement point can be realized.

[0021] Example Taking the analysis of vibration sources and transmission paths of multiple mechanical equipment inside a ship as an example, three main equipment are selected as vibration sources. Two vibration source measurement points are selected near the foot of each equipment and the vibration acceleration signal is used to represent the vibration source; two hydroacoustic measurement points are selected at different locations in the water outside the ship and the sound pressure signal is used to represent the target response. First, each equipment is turned on separately to calculate the transfer function between the sources. Then, the three devices are operated simultaneously to form different operating conditions (the number of operating conditions is d =8), synchronously measure and construct the acceleration response matrix of the coupled vibration measurement points , target sound pressure response measurement point matrix , and then the iterative Lanczos TTLS algorithm is used to obtain the transmissibility matrix of the OTPA method T m×n Finally, the sound pressure responses from the three devices (6 path points) to the target point outside the ship are synthesized, and the contribution of each vibration source to the target point is realized, as well as the identification and positioning of the main vibration source and transmission path.

[0022] The ill-posed problem in the OTPA method requires regularization optimization in the complex domain. In order to test the actual effect of the truncated TTLS algorithm in the complex domain, a complex coefficient matrix is ​​constructed. Where, Where, is the Hilbert matrix, , Take all rows, Pick ,Right now Representation matrix of Line and Matrix consisting of columns. Unknown parameters , their truth values ​​are . Add random noise to the coefficient matrix and observation items, and the noise level and The TTLS algorithm is compared with the commonly used regularized LS method, and the calculation results are shown in the following table. It can be seen that the error of the calculation result of the truncated total least squares method that considers both the coefficient matrix and the observation term errors is significantly smaller than that of the classic RLS method that does not consider the influence of the coefficient matrix noise.

[0023] Here, we use the coupled vibration source signal ( C input) and the source signal to eliminate the coupling between sources ( S The test analysis shows that the vibration signal of the equipment is a broadband signal. Here, the 1# target measurement point is given in 1 / 3 octave, such as Figure 1 shown.

[0024] Depend on Figure 1 It can be seen that: with cross-coupled signal C When used as a vibration source, due to the cross-coupling effect of other vibration sources, the OTPA synthesis results have a large error compared to the results when the device is running alone. The 2# device is more strongly coupled by the 1# device, resulting in a larger synthesis value. The 3# is in an independent cabin and is less coupled by other vibration sources, resulting in a smaller error. S As an input vibration source, it can effectively avoid the influence of cross-coupling between vibration sources. The noise synthesis value of the target point is consistent with the measured result. Except for a few abnormal fluctuation points (because the speed when opening the single opening is not completely consistent with that when opening the full opening or there is a slight deviation, resulting in errors), the rest of the errors are within 3dB, meeting the basic requirements of underwater vibration and noise analysis. Figure 2 This is the contribution vector diagram of each device to the 1# target point at a certain peak frequency point. It can be seen that the host and 1# device play an increasing role in the total synthesis of the target point. Figure 3 The contribution graph of each device to the target point shows that the vibration contribution of the three devices is ranked as device 1 > device 2 > device 3. This conclusion demonstrates the effectiveness of the OTPA method in vibration source identification, contribution analysis, and sound field prediction for coupled mechanical equipment.

Claims

1. A ship mechanical vibration source OTPA method for eliminating inter-source coupling and ill-posed problems, characterized by: The method is specifically as follows: 1) Determine the target of mechanical equipment working condition transfer path analysis, select at least one mechanical equipment m Vibration source measurement points and n target measuring points; When the mechanical equipment is turned on individually, s i ( t ) indicates the i The vibration source measurement point signal of each vibration source measurement point when the mechanical equipment is running independently, i =1, 2, ... m ; When the mechanical equipment is turned on at the same time, c i ( t ) indicates the i The mixed vibration signal of the vibration source measurement point, i =1, 2, ... m ; 2) Constructing a matrix of independent vibration source measurement points and mixed source signal matrix , solve the transfer function matrix ; 3) Combination d Mixed vibration signal matrix of vibration source measurement points for simultaneous operation measurement of mechanical equipment , target measurement point matrix and the transfer function matrix , using the truncated total least squares regularization algorithm to solve the transmissibility matrix T m×n ; 4) Then, based on the mixed signal of the vibration source measurement point of the mechanical equipment measured under any working condition , find the target measurement point response value of the corresponding working condition , thereby realizing the vibration contribution analysis, vibration source identification and sound field prediction of each vibration source measurement point to the target measurement point.

2. The OTPA method for ship mechanical vibration sources for eliminating inter-source coupling and ill-posed problems according to claim 1 is characterized by: In the step 1), , For the From the vibration source measuring point to the The response function of the propagation path between the vibration source measurement points is: represents the time point of the input signal history, Expressed as The vibration source measurement point signal at the time point, N Indicates the number of time points; And the mixed vibration signal c i ( t ) is converted to frequency domain and expressed as , represents the frequency, where For the From the vibration source measuring point to the The frequency response function between the vibration source measurement points is: Indicates the frequency domain value of the vibration source measurement point.

3. The OTPA method for ship mechanical vibration sources for eliminating inter-source coupling and ill-posed problems according to claim 1 is characterized by: In step 2), an independent vibration source measurement point matrix is ​​constructed. and mixed source signal matrix , solve the transfer function matrix The process is: When any mechanical equipment is turned on individually, it is recorded as one working condition, and the following conditions are turned on in sequence: r Mechanical equipment is recorded as r Working conditions, r Greater than or equal to m , and according to the equation , expressed as a matrix r The mixed vibration source signal matrix of the mixed vibration source signal and the vibration source measurement point signal of each working condition , independent vibration source measurement point matrix , and satisfies ; Independent vibration source measurement point matrix Chinese elements For the a Working condition, j Independent vibration source measurement point signals, satisfying j ≠ a hour , a =1, 2, ... r ; Mixed source signal matrix Chinese elements For the a Working condition, i Mixed vibration signals of vibration source measuring points; is the transfer function matrix, where the elements are ; Solving the transfer function matrix .

4. The OTPA method for ship mechanical vibration sources for eliminating inter-source coupling and ill-posed problems according to claim 1 is characterized by: The specific process of step 3) is as follows: When mechanical equipment is running at the same time, select d Different operating conditions, d Greater than or equal to m , through the transmission rate matrix T m×n , establish the vibration source measurement point matrix Target measurement point matrix The relationship between the two is established to establish the OTPA basic equation to remove the coupling between sources. ; Vibration source measurement point matrix Each column is the response value of all independent vibration source measurement points corresponding to the same working condition, and each row represents a working condition; the target measurement point matrix Each column in is the response value of all target measurement points corresponding to the same working condition, and each row represents a working condition; Since the vibration source measurement point matrix Cannot be obtained directly, by transferring the function matrix , combined with the mixed vibration signal matrix of the vibration source measurement point ,get ; Solving the transmissibility matrix using the truncated total least squares regularization algorithm T m×n .

5. The OTPA method for ship mechanical vibration sources for eliminating inter-source coupling and ill-posed problems according to claim 4 is characterized by: The transmissibility matrix is ​​solved by using the truncated total least squares regularization algorithm. T m×n The specific steps are as follows: 31) According to Equation, for l The target measuring point is n = l ( l =1,2,……, n ), build the augmented matrix , and perform singular value decomposition into: In the formula, the superscript " H " represents the matrix conjugate transpose, the matrix Each column vector in ( i =1,2,……, m ) orthogonal, matrix Each column vector in ( j =1,2,……, n +1) Orthogonal, diagonal matrix The diagonal elements of ; 32) The matrix Split into sub-matrices in k is the truncation parameter, represents a complex field; 33) The truncation parameter is k When , the TTLS regularized solution ; 34) Combine the generalized cross-validation criterion and the AIC information criterion to establish the equation , calculate the cutoff parameter k， The filter factor correction coefficient , express of elements; 35) Calculate the truncation parameter k Then, bring it into step 33) to find the corresponding l TTLS regularization solution for target measurement points ; 36) Repeat steps 31) to 35) to find all n The transmissibility matrix corresponding to the target measurement points .

6. The OTPA method for ship mechanical vibration sources for eliminating inter-source coupling and ill-posed problems according to claim 3, characterized in that: In the step 2), when there is a mechanical device that cannot be turned on independently, excitation is applied at the vibration source measuring point on the mechanical device that cannot be turned on by means of artificial excitation.

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