An Identification Method for the “Effective Coupling Loss Factor” Based on the Hybrid FE-SEA Model

Round 1

Reviewer 1 Report

kind authors,

the paper is very long, it should be shortened.

you have entered many formulas, but your contribution to the development of the SEA is not clear.

The quality of the figures needs to be improved.

Before proceeding with the revision the paper must be reviewed.

Highlight your contribution

Did you write the processing code in matlab?

You must specify your contribution to the development of the code you have written.

You need to better describe the test you performed

You need to better describe the results you have achieved.

Thanks for your attention

Author Response

Reviewer1

Comments and Suggestions for Authors

kind authors,

• the paper is very long, it should be shortened.

The submission type for this article is a long research paper. From the point of view of the comprehensiveness of the research, this paper is suitable for long articles.

2-you have entered many formulas, but your contribution to the development of the SEA is not clear.

In Chapter 3, Chapter 31.-3.5, the response of the three-coupling system is solved respectively. The multi-coupled system response is solved, so the multi-system coupling matrix is solved, and the ill-conditioned matrix of the coupling matrix is modified by principal element. This is an advance for solving the hybrid FE-SEA model.

 

3-The quality of the figures needs to be improved.

The picture in the image has been changed for clarity.

4-Before proceeding with the revision the paper must be reviewed.

According to the reviewer's opinion, the article has been reviewed and modified.

 

5-Highlight your contribution

Chapter 3.1-3.5 improved the coupled matrix solution method of the mixed model, which is the focus of the paper.

6-Did you write the processing code in matlab?

You must specify your contribution to the development of the code you have written.

As for the solution of mixed model multi-system, it is complicated at present and can only be solved by commercial software.

7-You need to better describe the test you performed

Line 551-562

As shown in Figure 7, the test device was built according to the 1:1 ratio between the model and the real object. The effective coupling loss factor was improved and verified.The test system is composed of physical sample, acceleration sensor, shaker, rope and test data line. Each measuring point on the surface of the physical sample was excited respectively, and the acceleration and velocity signals of each measuring point were tested.The shaker selects sinusoidal peak force of 100N and frequency range of 5-10KHz. 9 measuring points were selected for each board of the physical sample, and each measuring point was tested for three times to obtain the average value. Acceleration sensor PCB, select ±50g, sensitivity 100mv/g. The acceleration and velocity of each measuring point and the force of each measuring point were measured by power input method. The input power and energy of each measuring point are calculated according to the statistical energy power input method.

• You need to better describe the results you have achieved.

In this paper, the energy flow method is adopted to establish a mixed FE-SEA model with three coupling systems and a multi-system coupling model to solve the intermediate frequency solving accuracy problem of the existing mixed FE-SEA model. The parameter identification of effective coupling loss factor in mixed FE-SEA model is studied. The system response of deterministic components and the energy response of stochastic subsystem in three coupled systems are derived. Based on the three coupling system models, the multi-system coupling system response solution method is extended. Aiming at the ill-posed matrix problem existing in the solution of energy specific density in the hybrid FE-SEA model with the existing technology, an improved principal component weighted correction method was applied by introducing intermediate variables and error transfer. The inverse matrix of energy density is modified to solve the singular value problem of ill-posed matrix. In order to further verify the effectiveness of the improved hybrid FE-SEA model parameter identification method, the calculation results of the effective coupling loss factors of each plate were compared. The results show that the effective coupling loss factor calculated by the mixed FE-SEA method has a singular solution at some frequency points, which is an invalid coupling matrix. In this paper, the principal element correction method is used to correct the inverse matrix of the ratio of subsystem energy to modal density in the coupling matrix. The effective coupling loss factors calculated are all effective coupling matrices. The effective coupling loss factors calculated by the improved mixed FE-SEA method at the frequency of 400-2000Hz have a high degree of fit with the test results, which verifies the effectiveness of the proposed method. Compared with the existing literature, the cumulative error caused by the application of theoretical analytical solution to the effective coupling loss factor in complex structures is avoided. In the calculation frequency range of 1000-2000Hz, the calculation accuracy of the frequency band is also improved, and the overall calculation error of the whole frequency band is less than 10%, which has a certain engineering application significance. It provides a solution to calculate the coupling loss factor of mixed FE-SEA model effectively.

 

Author Response File: Author Response.doc

Reviewer 2 Report

The paper presents a method to solve the problem of medium frequency acoustic vibrations based on the hybrid model of finite element-statistical energy analysis (FE-SEA).

The manuscript needs to be improved, clarification and completions are necessary.

Please select the type of the paper (Article, Review, Communication, etc.).

Define abbreviations and acronyms the first time they are used in the text, even after they have been defined in the abstract. Do not use abbreviations in the title or heads unless they are unavoidable.

Line 541: "The effective coupling loss factor was improved and verified." How? You need to provide more details.

Describe the measurement procedure in more detail. At what point in time? How is the measuring setup set up? How many repetitions of measurements? What statistical methods are used to process experimental results? Describe the experimental stand in more detail. What method of experiment planning is used and why?

The conclusions should be based on the results obtained and not general statements. You should use values to justify statements from conclusions.

Author Response

Reviewer2

 

Comments and Suggestions for Authors

The paper presents a method to solve the problem of medium frequency acoustic vibrations based on the hybrid model of finite element-statistical energy analysis (FE-SEA).

 

1-Please select the type of the paper (Article, Review, Communication, etc.).

Article

 

• Define abbreviations and acronyms the first time they are used in the text, even after they have been defined in the abstract. Do not use abbreviations in the title or heads unless they are unavoidable.

FE-SEA is a professional abbreviation that is commonly used in the field. It is recommended to keep this notation.

 

• Line 541: "The effective coupling loss factor was improved and verified." How? You need to provide more details.

Chapter 3.5 explains it in detail. The ill - condition matrix of coupling matrix is modified by principal element. The problem of solving ill-conditioned matrix with effective coupling loss factor is improved. See Figures 5 and 6 for details

 

• Describe the measurement procedure in more detail. At what point in time? How is the measuring setup set up? How many repetitions of measurements? What statistical methods are used to process experimental results? Describe the experimental stand in more detail. What method of experiment planning is used and why?

Line 551-562

As shown in Figure 7, the test device was built according to the 1:1 ratio between the model and the real object. The effective coupling loss factor was improved and verified.The test system is composed of physical sample, acceleration sensor, shaker, rope and test data line. Each measuring point on the surface of the physical sample was excited respectively, and the acceleration and velocity signals of each measuring point were tested.The shaker selects sinusoidal peak force of 100N and frequency range of 5-10KHz. 9 measuring points were selected for each board of the physical sample, and each measuring point was tested for three times to obtain the average value. Acceleration sensor PCB, select ±50g, sensitivity 100mv/g. The acceleration and velocity of each measuring point and the force of each measuring point were measured by power input method. The input power and energy of each measuring point are calculated according to the statistical energy power input method.

 

 

• The conclusions should be based on the results obtained and not general statements. You should use values to justify statements from conclusions.

In this paper, the energy flow method is adopted to establish a mixed FE-SEA model with three coupling systems and a multi-system coupling model to solve the intermediate frequency solving accuracy problem of the existing mixed FE-SEA model. The parameter identification of effective coupling loss factor in mixed FE-SEA model is studied. The system response of deterministic components and the energy response of stochastic subsystem in three coupled systems are derived. Based on the three coupling system models, the multi-system coupling system response solution method is extended. Aiming at the ill-posed matrix problem existing in the solution of energy specific density in the hybrid FE-SEA model with the existing technology, an improved principal component weighted correction method was applied by introducing intermediate variables and error transfer. The inverse matrix of energy density is modified to solve the singular value problem of ill-posed matrix. In order to further verify the effectiveness of the improved hybrid FE-SEA model parameter identification method, the calculation results of the effective coupling loss factors of each plate were compared. The results show that the effective coupling loss factor calculated by the mixed FE-SEA method has a singular solution at some frequency points, which is an invalid coupling matrix. In this paper, the principal element correction method is used to correct the inverse matrix of the ratio of subsystem energy to modal density in the coupling matrix. The effective coupling loss factors calculated are all effective coupling matrices. The effective coupling loss factors calculated by the improved mixed FE-SEA method at the frequency of 400-2000Hz have a high degree of fit with the test results, which verifies the effectiveness of the proposed method. Compared with the existing literature, the cumulative error caused by the application of theoretical analytical solution to the effective coupling loss factor in complex structures is avoided. In the calculation frequency range of 1000-2000Hz, the calculation accuracy of the frequency band is also improved, and the overall calculation error of the whole frequency band is less than 10%, which has a certain engineering application significance. It provides a solution to calculate the coupling loss factor of mixed FE-SEA model effectively.

 

 

Author Response File: Author Response.doc

Round 2

Reviewer 2 Report

The authors responded to all my requests.