Analysis and Optimization of an Expansion Energy-Absorbing Anti-Crawler for Rail Vehicles
Round 1
Reviewer 1 Report
The writing of this paper is good, but the contents have some major weakness:
1、The theoretical methods in this paper lack innovation and the research is not in-depth enough.
2、The second part of the article has less experimental data, lacks effective experimental data to verify the correctness of theoretical research, and lacks rationality.
3、In the second part of the paper, when the finite element results are compared with the experimental results, there is a lack of discussion on the frequency domain.
4、The optimization algorithm used in the fourth part of the article is relatively simple, and it is recommended to update the algorithm.
5、The results after algorithm optimization have no actual experiments to verify their accuracy, so the article lacks scientificity and completeness.
6、The parameter T and α settings in Table 2 should be more precise, such as increasing the number of groups.
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Reviewer 2 Report
In this paper, the analysis and optimization of an anti-crawler for rail vehicles were studied. The finite element model established for optimization was verified by experimental testing. This paper is completed, while it still should be strengthened before publication.
In Figure 7, the maximum force value is slightly different. The reason for this situation should be discussed.
Equation (1) is mathematically incorrect. The upper limit of the integral should be described with a symbol other than “a”.
In figure 8, the curve names are misspelled. (mian)
In Equation 9, it is not necessary to give the lower limit of 585 kN for the average force.
In metamodeling, the artificial neural network method can provide better convergence. The comparison would be appropriate.
Heuristic optimization methods of optimizing energy-absorbing parts are often preferred. One of the these methods can be preferred and the results can be compared with SQP. Some examples of related methods:
· Optimization design for circular multi-cell thin-walled tubes with discrete and continuous design variables. Mechanics of Advanced Materials and Structures, Doi: 10.1080/15376494.2022.2111735
· Crashworthiness analysis and multiobjective robust optimization of two-stage variable thickness expansion tube under impact loading. Structural and Multidisciplinary Optimization, Doi: 10.1007/s00158-022-03267-0
Author Response
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Reviewer 3 Report
Review for Manuscript ID: sustainability-2160097
Analysis and optimization of an expansion energy-absorbing anti-crawler for rail vehicle
By Z. Zhao, P. Xu
The manuscript investigates an absorber. An experiment is shown . A finite element model is given. The test is simulated and an overall agreement is demonstrated. The model is used to analyse the influence of the design variables thickness, angle and friction. Optimized design parameters have been searched and found.
1. The dynamics of the impact should be discussed. What is the behaviour of the rigid wall mass? What is behind the absorber, another mass? What is the behaviour of the decelerated mass.
2. What is the excitation of the model?
3. The problem strongly depends of the plastic behaviour of the tube material. The material law should be given and discussed. Give arguments for Your choice.
4. The agreement between experiment and simulation is for the (tunable) final force value and for the rise time. The dynamic behaviour is different. This must be clearly stated.
5. The rest of the analysis seems to be alomost quasi-static. Has the influence of the penetration speed been analysed?
6. Some arguments for the chosen optimisation quantitiy should be given. Section 3.1.1 is not enough and has too many citations without details.
7. Moreover the symbol alfa has two meanings.
8. A list of symbols and of abbreviations should be given.
Author Response
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Round 2
Reviewer 1 Report
The ordering of parameters T in Tables 3 and 4 should be standardized.
Author Response
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Reviewer 2 Report
The authors made the relevant corrections.
Author Response
Thank you very much for your comments and suggestions
Reviewer 3 Report
Review for Manuscript ID: sustainability-2160097 1. Revision
Analysis and optimization of an expansion energy-absorbing anti-crawler for rail vehicle
By Z. Zhao, P. Xu
Thank You for the additional information.
1. The sections about the test need proof reading and corrections. There are many mistakes.
2. Check the axles labels (time – displacement).
3. Give some checks about the quantities displacement, velocity, acceleration, force in the text. Something seems to be inconsistent (for example the velocity in Fig. 6).
4. The excitation of the finite-element model is not given.
5. Is the trolley mass included in the finite-element model?
6. The list of symbols should be alphabetically ordered.
Author Response
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Round 3
Reviewer 3 Report
Review for Manuscript ID: sustainability-2160097 2. Revision
Analysis and optimization of an expansion energy-absorbing anti-crawler for rail vehicle
By Z. Zhao, P. Xu
Now, things are clearer. Some minor recommendations:
1. You say „end of collision“ but the speed is still 5.2 m/s? How does the collision really end (with v = 0)? A sentence could clarify the confusion.
2. You could add the check „E1-E2=m/2(v1^2-v2^2)=Fs=128kJ“
3. How many tubes are used in the experiment and how much energy is absorbed per tube?
4. Explain the purpose of the absorber? Only a small part of the energy of the car is absorbed in the experiment.
Author Response
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