The Mesoscopic Numerical Simulation of GAP/CL20/AP Composite Solid Propellant Based on MPM and FEM
Round 1
Reviewer 1 Report
The manuscript "Mesoscopic numerical simulation of GAP/CL20/AP composite solid fuel based on MPM and FEM" (ID applsci-2265244) deals with a topic in the broad scope of the journal, it is indeed applied science, applied numerical modeling to predict crack initiation and debonding in a solid propellant used in rocket engines.
The manuscript communicates well its message qualitatively: the abstract conveys the results of the article, is concise, however, it does not gives quantitative results or specifics about the utility and novelty of the reported simulation.
HTPB is not defined at first use.
The introduction is informative about the basics of the used method, but is not updated, the global research is not presented and also the quality of recent citations should be improved. The novelty indicated is the application of a numerical model to GAP/CL20/AP composite. However the significance of this is not clear.
Methods are described with great length on some minor details, which are of general knowledge. Instead the addition of specific details on the numerical simulation and updated references would be of great help, even if the details are not included in the manuscript itself but as supplementary information. The specifics of the numerical simulation would be important for the readers directly interested in this manuscript, even though not essential for most of the readers to understand the results. The use of proprietary commercial software and the unknown script codes make the replication of this work by other researchers a difficult task, so I suggest the authors to be more open in sharing the simulation method, because it is the key result of the study and should be reflected in the content of the manuscript.
The results are presented clearly, include sufficient graphs that help readers visualize the data.
The conclusions are supported by and logically derived from the presented results.
The limitations of the used method to reproduce experimental data are carefully overcome, as demonstrated by the good correlation between model and experiment for the chosen case of study, however the three parameters of the model should be more clearly related to real physical and experimental variables. In this sense it remains unclear the applicability of the study, except for experimental conditions very similar to those presented in the manuscript. Meso-debonding is a common failure mechanism in composite solid propellants, initiated by the build-up of stress within the propellant due to thermal and mechanical loads. This stress can cause micro-cracks to form at the interface between the solid particles and the binder. Over time, these micro-cracks can grow and coalesce, leading to the formation of meso-cracks. Once meso-cracks form, the binder and the solid particles are no longer fully bonded, and the propellant may start to show signs of degradation. This can lead to reduced mechanical properties and a decrease in the overall performance of the rocket engine. To prevent meso-debonding, researchers and engineers use a variety of techniques, such as modifying the binder chemistry, changing the processing conditions, and adding other additives to the propellant. The authors should relate their findings with specific techniques to prevent meso-debonding in the chosen system.
Overall, the manuscript can be significantly enhanced before publication.
Author Response
Dear professor：
thank you for your advice，Please see the attachment.
With best regards to you and your classmates.
Yours sincerely
Author Response File: 
Author Response.pdf
Reviewer 2 Report
It can be accepted in the present form
Author Response
Dear professor, thank you for your approval of my thesis.
With best regards to you
Yours sincerely
Reviewer 3 Report
This study systematically carried out the meso-damage experiment of composite propellant and the numerical simulation study of its mechanical behavior.
1. In the paper, the simulation results are in good agreement with the experimental results in the previous study. however, this study only carried out computational simulations. the simulation results could be or would be tuned by the user's settings (e.g. magnitude of force) to get better results. In order to free of this issue, authors should provide clear and specific procedures and assumptions for the simulation and verification(including validation)
2. The discussion section is insufficient to emphasize their contribution. This section should be enlarged.
3. The limitation section should be added for future works.
4. Overall logical flow of the manuscript should be more smooth.
Author Response
Dear professor：
thank you for your advice. Please see the attachment.
With best regards to you.
Yours sincerely,
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
The limitations and innovation of the study, as well as the need for future studies, were identified.
Reviewer 3 Report
Thanks for your response.
Good luck.
