Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This manuscript provide a brief review on the micro heat exchangers in food and pharmaceutical Industries. Although it is well writen, there is no significant improvement on the summary of MHEs. The innovative design of MHEs and performance enhanced technique are not well summarized. Lot of references are not included and discussed. For example, the literature number is much more than those presented in Fig. 4. The microchannel heat sinks should be also included.

Author Response

Dear Reviewer,

Thank you for your thorough and constructive review of our manuscript. We sincerely appreciate the time and expertise you have dedicated to evaluating our work. Please find our responses to the comments below, addressed one by one. Below, we provide a point-by-point response to each comment, detailing the revisions made in the manuscript.

Reviewer #1:

Comments 1: Although it is well writen, there is no significant improvement on the summary of MHEs. The innovative design of MHEs and performance enhanced technique are not well summarized.

Response 1: We are thankful to the reviewer for this precise feedback. The manuscript has been revised accordingly. (See Page 9, Line 241-254; Page 16, Line 481-495; Page 30, Line 1053-1073 ).

Comments 2: Lot of references are not included and discussed. For example, the literature number is much more than those presented in Fig. 4.

Response 2: Thanks. We thank the reviewer for this comment. In the revised manuscript, the literature coverage has been substantially expanded, and the total number of cited references has increased from 112 to 139, ensuring a more comprehensive discussion of recent and relevant studies on micro heat exchangers.

It is clarified that Figure 4 is intended to present a representative classification of micro heat exchanger research, rather than an exhaustive depiction of all cited literature. Many additional references focus on performance analysis, enhancement techniques, materials, applications, and manufacturing aspects, which are now discussed throughout the corresponding sections of the manuscript but are not individually shown in Figure 4.

Comments 3: The microchannel heat sinks should be also included.

Response 3: We thank the reviewer for this suggestion. The manuscript has been revised accordingly. (See Page 6, Line 164-172; Page 7, Line 175-181).

Comments 4: The English could be improved to more clearly express the research.

Response 4: We thank the reviewer for this suggestion. The manuscript has been carefully reviewed and revised to improve the clarity, readability, and overall quality of the English language. Necessary corrections and refinements have been made throughout the text to ensure that the research is expressed more clearly and professionally.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The peer-reviewed manuscript represents a relevant contribution to the scientific community, from the review paper point of view. The systematic review is complete and provides solid evidences, being worthy of publication in Inventions.

However, there are some missing points that should be addressed before accepting the manuscript for publication.

1. You are missing important recent contributions in the field, related to vortex shedding-based microheat exchangers. Please see and discuss in the manuscript:

https://doi.org/10.1007/s10404-013-1137-5

https://doi.org/10.1016/j.euromechflu.2021.12.004

https://doi.org/10.1016/j.ijheatmasstransfer.2009.10.013

https://www.mdpi.com/2072-666X/11/7/668

2. Please discuss in the conclusions section the impact on innovation of each MHX. A bunch of bullet points does not summarize this.

3. The discussion of Figure 13 is not clear at all. Please clarify and explain more clear each feature. Explain what flow maldistribution actually is and give an example.

4. What coloured lines (different gray intensity) in Figure 9 means? Maybe good to redo this figure.

Author Response

Dear Reviewer,

Reviewer #2:

However, there are some missing points that should be addressed before accepting the manuscript for publication.

Comments 1: You are missing important recent contributions in the field, related to vortex shedding-based microheat exchangers. Please see and discuss in the manuscript:

https://doi.org/10.1007/s10404-013-1137-5

https://doi.org/10.1016/j.euromechflu.2021.12.004

https://doi.org/10.1016/j.ijheatmasstransfer.2009.10.013

https://www.mdpi.com/2072-666X/11/7/668

Response 1: We thank the reviewer for highlighting these important contributions. The manuscript has been revised to include a dedicated and expanded discussion on vortex shedding–based micro heat exchangers. The suggested references have been added and discussed in the revised manuscript. A new paragraph has been added in the “Micro Heat Exchangers” section 2 (See Page 7, Line 206-209; Page 8, Line 210-238), with additional reinforcement in the Section 4 “Factors Affecting the Performance of MHEs - Channel Geometry” subsection, to explicitly explain the role of vortex shedding mechanisms in enhancing heat transfer at the microscale. (See Page 14, Line 432-434; Page 16, Line 481-495).

Comments 2: Please discuss in the conclusions section the impact on innovation of each MHX. A bunch of bullet points does not summarize this.

Response 2: We are very much thankful to the reviewer for this valuable suggestion. The conclusions section has been substantially revised by removing the bullet-point format and replacing it with an integrated, paragraph-based discussion. The revised Conclusions now explicitly analyze the innovation impact of different micro heat exchanger (MHX) concepts, including conventional microchannel designs, geometrically enhanced and vortex-inducing configurations, nanofluid-assisted systems, and manufacturing-driven innovations. (See Page 29, Lines 1053-1073).

Comments 3: The discussion of Figure 13 is not clear at all. Please clarify and explain more clear each feature. Explain what flow maldistribution actually is and give an example.

Response 3: We thank the reviewer for this important comment. In the revised manuscript, the figure previously referred to as Figure 13 has been renumbered as Figure 15 due to the inclusion of additional material. The discussion associated with this figure has been substantially revised and expanded to improve clarity. (See Page 25, Lines 875-908).

Comments 4: What coloured lines (different gray intensity) in Figure 9 means? Maybe good to redo this figure.

Response 4: We thank the reviewer for this helpful suggestion. In the revised manuscript, the figure previously referred to as Figure 9 has been renumbered as Figure 11 due to the inclusion of additional material. The revised Figure 11 is included in the revised manuscript and is also provided here for reference. (See Page 15, Lines 469-470)

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The manuscript entitled “A Review of Recent Advances in Micro Heat Exchangers in the Food and Pharmaceutical Industries” is excessively long and should be reduced by at least half. In its current form, the paper exceeds 30 pages, which makes it difficult to read and follow. Moreover, the review lacks sufficient synthesis and does not provide rigorous comparative analysis supported by tables or figures. A more concise structure, combined with clearer comparisons and summarized insights, would significantly improve its readability and overall impact.

In its present version, it is difficult to recommend acceptance of the manuscript.

There are several additional comments that need to be addressed:

In the title, please replace “Industries” with “industries”.
Line 39: Please replace “heat and mass transfer” with “Heat transfer”. In a heat exchanger, there is no mass transfer between the two fluids.
Figure 1: Please replace “Hear Exchanger” with “Heat Exchanger”. Additionally, move Figure 1 to immediately follow the paragraph beginning with “Figure 1 presents an overview of the global…”.
Line 59: Please define the abbreviation “HVAC” at its first occurrence (Heating, Ventilation, and Air Conditioning).
Figure 2: Please add “HX” after “Heat Exchanger,” and replace “Dh” with “D_h” (with h in subscript) in all four occurrences. Moreover, the font size used in the figure should be increased to improve readability. Additionally, move Figure 2 to immediately follow the paragraph beginning with “Heat exchangers can be classified into different…”.
Line 160: Remove “S.S.” and “a micro-channel heat exchanger”. Replace “(MCHEs)” with “MCHEs”.
Line 165: Remove “Microchannel heat sinks” and replace “(MCHS)” with “MCHS”.
Line 172: Please replace “heat sink. [23]” with “heat sink [23].”
Line 191: Please add a full stop at the end of Figure 6’s title.
Table 1: Please move Table 1 to immediately follow the paragraph beginning with “Micro heat exchangers are essential to the food…”. Additionally, please update the reference numbers throughout the text, as relocating the table will affect their order. The abbreviation “API” should be defined at its first occurrence.
Figure 8: Please move Figure 8 to immediately follow the paragraph beginning with “The food industry consumes…”.
Line 356: replace “MHE” with “MHX”.
Line 379: add “%” after “20.75”.
Figure 9: Please move Figure 8 to immediately follow the paragraph beginning with “It can be seen that in Figure 9, the energy consumption…”.
Lines 388-390: Please remove the sentence: “Sterility can be defined as ‘the quality or condition of being sterile,’ where sterile is defined as being ‘free from living organisms and especially pathogenic microorganisms,’” since the sterilization process has already been discussed earlier.
Line 424: Replace “MHE” with “MHX”.
Line 427: Add “{MCHE)” after “Microchannel heat exchangers”.
Figure 11: This figure is not cited in the manuscript. In addition, the figure quality is unclear and should be improved for better readability.
Line 483: replace “[70], [71]” by “[70, 71]”.
Pages 16–18: Please add table(s) comparing all the cited works. This will improve clarity and make the discussion more concise and accessible.
Line 551: Please add “(MPHX)” after “microplate heat exchanger”.
Line 566: Please replace “Al2O3” with “Al₂O₃” in both occurrences, using subscripts for “2” and “3”.
Line 585: Please replace “Nusselt, Reynolds, and Knudsen numbers” with “Nusselt (Nu), Reynolds (Re), and Knudsen (Kn) numbers”
Line 396: replace “Fe2O₃” with “Fe₂O₃”, using subscripts for “2” and “3”.
A list of abbreviation should be added to the manuscript.
Line 630: replace “Al2O3” with “Al₂O₃”, using subscripts for “2” and “3”.
Figures 12, 13, 14, and 15: The figures are not clear and should be improved for better readability.
Line 897: Please check whether “HE” is correct, or if it should be “HX”.
Table 3: Please move Table 3 to immediately follow the paragraph beginning with “Micro heat exchangers play a crucial role …”.

Figure 16: Please move Figure 16 to immediately follow the paragraph beginning with “Surface treatm

Author Response

Dear Reviewer,

We sincerely thank the reviewer for the thorough and productive evaluation of our manuscript. We greatly appreciate the time and expertise dedicated to reviewing our work. Below, we provide a point-by-point response to each comment, along with the corresponding revisions made in the manuscript. All changes in the revised manuscript have been highlighted in yellow for easy identification. Please note that the line numbering has changed due to revisions made in the manuscript.

The manuscript entitled “A Review of Recent Advances in Micro Heat Exchangers in the Food and Pharmaceutical Industries” is excessively long and should be reduced by at least half. In its current form, the paper exceeds 30 pages, which makes it difficult to read and follow. Moreover, the review lacks sufficient synthesis and does not provide rigorous comparative analysis supported by tables or figures. A more concise structure, combined with clearer comparisons and summarized insights, would significantly improve its readability and overall impact.

In its present version, it is difficult to recommend acceptance of the manuscript.

There are several additional comments that need to be addressed:

Authors’ Response: Thank you for your insightful feedback. The manuscript has been carefully revised to improve clarity, structure, and synthesis of the reviewed studies. Several sections have been condensed and reorganized to enhance readability, and comparative tables have been added to summarize key findings from the cited literature and provide clearer comparisons among studies. These revisions were made to improve the overall coherence and accessibility of the manuscript while maintaining the completeness of the review.

Comments 1: In the title, please replace “Industries” with “industries”.

Response 1: Thank you for your helpful suggestion. The title has been corrected accordingly, and the word “Industries” has been changed to “industries” in the revised manuscript. (See Page 1, Line 3).

Comments 2: Line 39: Please replace “heat and mass transfer” with “Heat transfer”. In a heat exchanger, there is no mass transfer between the two fluids.

Response 2: Thank you for your valuable comment. The keyword “heat and mass transfer” has been revised to “Heat transfer” to accurately describe the mechanism occurring in heat exchangers, where no mass transfer occurs between the two fluids. (See Page 2, Line 41).

Commentsc3: Figure 1: Please replace “Hear Exchanger” with “Heat Exchanger”. Additionally, move Figure 1 to immediately follow the paragraph beginning with “Figure 1 presents an overview of the global…”.

Response 3: Thank you for your valuable comment. The typographical error “Hear Exchanger” has been corrected to “Heat Exchanger” in Figure 1. Additionally, Figure 1 has been repositioned to immediately follow the paragraph as suggested. (See Page 3, Line 69).

Comments 4: Line 59: Please define the abbreviation “HVAC” at its first occurrence (Heating, Ventilation, and Air Conditioning).

Response 4: Thank you for your valuable suggestion. The abbreviation HVAC has now been defined at its first occurrence as Heating, Ventilation, and Air Conditioning (HVAC) in the revised manuscript. (See Page 2, Line 57-58).

Comments 5: Figure 2: Please add “HX” after “Heat Exchanger,” and replace “Dh” with “Dh” (with h in subscript) in all four occurrences. Moreover, the font size used in the figure should be increased to improve readability. Additionally, move Figure 2 to immediately follow the paragraph beginning with “Heat exchangers can be classified into different…”.

Response 5: Thank you for your valuable comment. The requested revisions have been implemented. The term “HX” has been added after “Heat Exchanger,” and “Dh” has been corrected to “Dₕ” (with h in subscript) in all four occurrences in Figure 2. In addition, the font size in the figure has been increased to improve readability. Furthermore, Figure 2 has been repositioned to immediately follow the paragraph beginning with “Heat exchangers can be classified into different…” in the revised manuscript. (See Page 4, Line 105).

Comments 6: Line 160: Remove “S.S.” and “a micro-channel heat exchanger”. Replace “(MCHEs)” with “MCHEs”.

Response 6: Thank you for your valuable comment. The terms “S.S.” and “a micro-channel heat exchanger” have been removed as suggested. Additionally, the abbreviation has been standardized to “MCHXs” throughout the manuscript to maintain consistency with the terminology used in the study. The correction has been implemented in the revised manuscript (See Page 6, Line 159-160).

Comments 7: Line 165: Remove “Microchannel heat sinks” and replace “(MCHS)” with “MCHS”.

Response 7: Thank you for your valuable comment. The term “Microchannel heat sinks” has been removed, and “(MCHS)” has been revised to “MCHS” as suggested. This correction has been implemented in the revised manuscript (See Page 6, Line 164-165).

Comments 8: Line 172: Please replace “heat sink. [23]” with “heat sink [23].”

Response 8: Thank you for your helpful comment. The punctuation has been corrected, and “heat sink. [23]” has been revised to “heat sink [23].” This correction has been implemented in the revised manuscript (See Page 6, Line 171).

Comments 9: Line 191: Please add a full stop at the end of Figure 6’s title.

Response 9: Thank you for your helpful comment. A full stop has been added at the end of the title of Figure 6 as suggested. This correction has been implemented in the revised manuscript (See Page 7, Line 194).

Comments 10: Table 1: Please move Table 1 to immediately follow the paragraph beginning with “Micro heat exchangers are essential to the food…”. Additionally, please update the reference numbers throughout the text, as relocating the table will affect their order. The abbreviation “API” should be defined at its first occurrence.

Response 10: Thank you for your valuable comment. Table 1 has been moved to immediately follow the paragraph as suggested. Accordingly, the reference numbers throughout the manuscript have been updated to maintain the correct sequence following the relocation of the table. (See Page 9, Line 251).

In addition, the abbreviation API has been defined at its first occurrence as “Active Pharmaceutical Ingredient (API)” in the revised manuscript. (See Page 31, Line 1041).

Comments 11: Figure 8: Please move Figure 8 to immediately follow the paragraph beginning with “The food industry consumes…”.

Response 11: Thank you for your helpful suggestion. Figure 8 has been repositioned to immediately follow the paragraph as recommended. This modification has been implemented in the revised manuscript. (See Page 10, Line 270).

Comments 12: Line 356: replace “MHE” with “MHX”.

Response 12: Thank you for your helpful comment. The abbreviation “MHE” has been corrected to “MHX” as suggested. This revision has been implemented in the revised manuscript after repositioning the table (See Page 9, Line 251).

Comments 13: Line 379: Add “%” after “20.75”.

Response 13: Thank you for your helpful comment. The symbol “%” has been added after “20.75” as suggested. This correction has been implemented in the revised manuscript (See Page 12, Line 346). Please note that the line numbering has changed due to revisions made in the manuscript.

Comments 14: Figure 9: Please move Figure 8 to immediately follow the paragraph beginning with “It can be seen that in Figure 9, the energy consumption…”.

Response 14: Thank you for your helpful comment. Figure 9 has been repositioned to immediately follow the paragraph as suggested. This modification has been implemented in the revised manuscript. (See Page 12, Line 353).

Comments 15: Lines 388-390: Please remove the sentence: “Sterility can be defined as ‘the quality or condition of being sterile,’ where sterile is defined as being ‘free from living organisms and especially pathogenic microorganisms,’” since the sterilization process has already been discussed earlier.

Response 15: Thank you for your valuable comment. The sentence defining “sterility” has been removed from the manuscript as suggested. The revision has been implemented in the revised manuscript.

Comments 16: Line 424: Replace “MHE” with “MHX”.

Response 16: Thank you for your helpful comment. The abbreviation “MHE” has been corrected to “MHX” as suggested. This revision has been implemented in the revised manuscript (See Page 13, Line 388). Please note that the line numbering has changed due to revisions made in the manuscript.

Comments 17: Line 427: Add “{MCHE)” after “Microchannel heat exchangers”.

Response 17: Thank you for your helpful comment. The abbreviation “(MCHE)” has been added after “Microchannel heat exchangers” as suggested. This revision has been implemented in the revised manuscript (See Page 13, Line 391). Please note that the line numbering has changed due to revisions made in the manuscript.

Comments 18: Figure 11: This figure is not cited in the manuscript. In addition, the figure quality is unclear and should be improved for better readability.

Response 18: Thank you for your valuable comment. Figure 11 has now been properly cited in the manuscript at the appropriate location in the text. (See Page 13, Line 400-401). Additionally, the quality and resolution of the figure have been improved to enhance readability in the revised manuscript. (See Page 14, Line 404-405).

Comments 19: Line 483: replace “[70], [71]” by “[70, 71]”.

Response 19: Thank you for your helpful comment. The citation format has been corrected, and “[70], [71]” has been revised to “[70, 71]” as suggested. This correction has been implemented in the revised manuscript (See Page 14, Line 434). Please note that the line numbering has changed due to revisions made in the manuscript.

Comments 20: Pages 16–18: Please add table(s) comparing all the cited works. This will improve clarity and make the discussion more concise and accessible.

Response 20: Thank you for your valuable suggestion. A comparative two-tables (Table 2 & Table 3) summarizing the key findings and characteristics of the cited studies has been added to the revised manuscript. (Table 2: See Page 15, Line 460; Table 3: See Page 17, Line 521).

Comments 21: Line 551: Please add “(MPHX)” after “microplate heat exchanger”.

Response 21: Thank you for your helpful comment. The abbreviation “(MPHX)” has been added after “microplate heat exchanger” as suggested. This revision has been implemented in the revised manuscript (See Page 15, Line 447). Please note that the line numbering has changed due to revisions made in the manuscript.

Comments 22: Line 566: Please replace “Al2O3” with “Al2O3” in both occurrences, using subscripts for “2” and “3”.

Response 22: Thank you for your helpful comment. The chemical formula “Al2O3” has been corrected to “Al₂O₃” with the appropriate subscripts for 2 and 3 in both occurrences. This revision has been implemented in the revised manuscript (See Page 16, Line 494). Please note that the line numbering has changed due to revisions made in the manuscript.

Comments 23: Line 585: Please replace “Nusselt, Reynolds, and Knudsen numbers” with “Nusselt (Nu), Reynolds (Re), and Knudsen (Kn) numbers”

Response 23: Thank you for your helpful comment. The text has been revised to “Nusselt (Nu), Reynolds (Re), and Knudsen (Kn) numbers” as suggested. This correction has been implemented in the revised manuscript (See Page 18, Line 523-524). Please note that the line numbering has changed due to revisions made in the manuscript.

Comments 24: Line 396: replace “Fe2O₃” with “Fe₂O₃”, using subscripts for “2” and “3”.

Response 24: Thank you for your helpful comment. The chemical formula “Fe2O3” has been corrected to “Fe₂O₃” with the appropriate subscripts for 2 and 3. This revision has been implemented in the revised manuscript. (See Page 18, Line 533). Please note that the line numbering has changed due to revisions made in the manuscript.

Comments 25: A list of abbreviation should be added to the manuscript.

Response 25: Thank you for your valuable suggestion. A list of abbreviations has been added to the revised manuscript. (See Page 31, Line 1014).

Comments 26: Line 630: replace “Al2O3” with “Al2O3”, using subscripts for “2” and “3”.

Response 26: Thank you for your helpful comment. The chemical formula “Al2O3” has been corrected to “Al₂O₃” with the appropriate subscripts for 2 and 3. This revision has been implemented in the revised manuscript (See Page 18, Line 560). Please note that the line numbering has changed due to revisions made in the manuscript.

Comments 27: Figures 12, 13, 14, and 15: The figures are not clear and should be improved for better readability.

Response 27: Thank you for your valuable comment. The quality and resolution of Figures 12, 13, 14, and 15 have been improved to enhance clarity and readability in the revised manuscript. The figures have been updated accordingly.

Comments 28: Line 897: Please check whether “HE” is correct, or if it should be “HX”.

Response 28: Thank you for your helpful comment. The abbreviation has been checked and corrected to “HX” to maintain consistency with the terminology used throughout the manuscript. This revision has been implemented in the revised manuscript. (See Page 25, Line 820). Please note that the line numbering has changed due to revisions made in the manuscript.

Comments 29: Table 3: Please move Table 3 to immediately follow the paragraph beginning with “Micro heat exchangers play a crucial role …”.

Response 29: Thank you for your helpful suggestion. The table has been moved to immediately follow the paragraph as recommended. Please note that due to revisions in the manuscript, Table 3 has been renumbered as Table 5 in the revised version. (See Page 27, Line 888).

Comments 30: Figure 16: Please move Figure 16 to immediately follow the paragraph beginning with “Surface treatm

Response 30: Thank you for your helpful suggestion. Figure 16 has been repositioned to immediately follow the paragraph as recommended. This modification has been implemented in the revised manuscript. (See Page 29, Line 932).

Comments 31: The English could be improved to more clearly express the research.

Response 31: We thank the reviewer for this suggestion. The manuscript has been carefully reviewed and revised to improve the clarity, readability, and overall quality of the English language. Necessary corrections and refinements have been made throughout the text to ensure that the research is expressed more clearly and professionally.

Reviewer 4 Report

Comments and Suggestions for Authors

1.Part of the English abbreviations appear for the first time without their full names marked, such as CFD in Line 30, HVAC in Line 59, HX in Line 101, etc. There are many similar situations throughout the entire text, and it is recommended to thoroughly review and revise them.

2.Only 4 keywords are listed in the keyword section, which is insufficient in quantity and coverage. It is recommended to supplement keywords that are strongly related to the core research content.

3.The keyword 'Micro heat exchangers' has a case inconsistency issue and should be uniformly changed to' Micro heat exchangers'. It is recommended to modify it.

4.The expression of some professional terms in the text is inconsistent, such as "micro heat exchangers" sometimes abbreviated as MHEs and sometimes abbreviated as MHXs. It is recommended to use a unified abbreviation and label it when it first appears (such as Micro heat exchangers, MHEs), and maintain consistency throughout the text to avoid confusion for readers.

5.The unit format of "1000 w/cm²" in line 159 is incorrect and should be in regular font.

6.There are multiple spelling and grammar errors in the text, such as “[25]. According to Kandlikar and Grande [26] have categorized heat exchanger channels as follows” in Line 180. There are also some sentences with inconsistent subject verb and unsmooth subordinate clause connections. It is recommended to read and proofread the entire text to correct spelling, grammar, and punctuation errors.

7.The description of 'such ad such as' in line 229 is incorrect, and there are also some similar errors throughout the text. It is recommended to thoroughly check and make corrections.

8.The format of the captions is not consistent, such as Figs. 7 and 10, it is suggested to make modifications.

9.Some key viewpoints lack literature support, such as "The food industry consumes about 30% of the energy used worldwide, which accounts for 20% of greenhouse gas emissions" in Line 276. It is recommended to supplement the literature support for key viewpoints, verify and revise the literature numbers.

10.Some chemical equations in the article are written incorrectly, such as Fe2O3 in Line 596 and Al2O3 in Line 630. Suggest a comprehensive inspection and modification.

11.In the classification section of micro heat exchangers, it is mentioned that they can be classified into conventional channels, mini channels, and micro channels according to size, but the industry standards or sources for this classification are not clear. There is confusion in the definition of the concepts of "micro heat exchangers (MHEs)" and "micro channel heat exchangers (MCHEs)", and some paragraphs mix the two without clearly explaining their inclusion relationship and differences. It is necessary to clarify the definition, classification standards, and sources of core concepts, and clarify the boundaries of easily confused concepts.

Author Response

Dear Reviewer,

Thank you very much for taking the time to review this manuscript. The comments you have provided are immensely helpful in further improving the quality of the manuscript. We have carefully considered all of your feedback. Below, we present a point-by-point response to each comment, indicating the revisions made in the manuscript. All modifications in the revised version have been highlighted in yellow for easy reference. Please note that line numbers may differ from the previous version due to the revisions made in the manuscript.

Comments 1: Part of the English abbreviations appear for the first time without their full names marked, such as CFD in Line 30, HVAC in Line 59, HX in Line 101, etc. There are many similar situations throughout the entire text, and it is recommended to thoroughly review and revise them.

Response 1: Thank you for your valuable comment. The manuscript has been carefully reviewed to ensure that all abbreviations are defined at their first occurrence, including Computational Fluid Dynamics (CFD), Heating, Ventilation, and Air Conditioning (HVAC), and Heat Exchanger (HX). (See Page 2, Line 32; Page 2, Line 57-58; Page 4, Line 105).

Similar cases throughout the manuscript have been corrected to improve clarity and consistency.

Comments 2: Only 4 keywords are listed in the keyword section, which is insufficient in quantity and coverage. It is recommended to supplement keywords that are strongly related to the core research content.

Response 2: Thank you for your valuable suggestion. The keyword section has been revised and expanded to include additional keywords that better reflect the core topics and scope of the study. (See Page 2, Line 41-43).

Comments 3: The keyword 'Micro heat exchangers' has a case inconsistency issue and should be uniformly changed to' Micro heat exchangers'. It is recommended to modify it.

Response 3: Thank you for your helpful comment. The case formatting of the keyword “Micro heat exchangers” has been corrected and standardized to ensure consistency in the keyword section. (See Page 2, Line 41-43).

Comments 4: The expression of some professional terms in the text is inconsistent, such as "micro heat exchangers" sometimes abbreviated as MHEs and sometimes abbreviated as MHXs. It is recommended to use a unified abbreviation and label it when it first appears (such as Micro heat exchangers, MHEs), and maintain consistency throughout the text to avoid confusion for readers.

Response 4: Thank you for your valuable comment. The manuscript has been carefully reviewed to ensure consistency in the use of abbreviations. The term Micro Heat Exchangers (MHXs) has been defined at its first occurrence and used consistently throughout the manuscript, replacing other inconsistent abbreviations such as MHEs. These revisions have been made to improve clarity and avoid confusion for readers.

Comments 5: The unit format of "1000 w/cm2" in line 159 is incorrect and should be in regular font.

Response 5: Thank you for your helpful comment. The unit formatting has been corrected, and “1000 w/cm²” has been revised to “1000 W/cm²” in regular font to follow standard scientific notation. (See Page 6, Line 159).

Comments 6: There are multiple spelling and grammar errors in the text, such as “[25]. According to Kandlikar and Grande [26] have categorized heat exchanger channels as follows” in Line 180. There are also some sentences with inconsistent subject verb and unsmooth subordinate clause connections. It is recommended to read and proofread the entire text to correct spelling, grammar, and punctuation errors.

Response 6: Thank you for your valuable comment. The entire manuscript has been carefully reviewed and thoroughly proofread to correct spelling, grammar, punctuation, and sentence structure issues, including the example mentioned in Lines 177-179. Several sentences have been revised to improve subject-verb agreement, clarity, and overall readability. Please note that line numbers may differ from the previous version due to the revisions made in the manuscript.

Comments 7: The description of 'such ad such as' in line 229 is incorrect, and there are also some similar errors throughout the text. It is recommended to thoroughly check and make corrections.

Response 7: Thank you for your valuable comment. The error “such ad such as” has been corrected in the revised manuscript. (See Page 8, Line 219).In addition, the entire manuscript has been carefully reviewed to identify and correct similar typographical and language errors throughout the text. All corresponding changes have been highlighted in yellow in the revised manuscript.

Comments 8: The format of the captions is not consistent, such as Figs. 7 and 10, it is suggested to make modifications.

Response 8: Thank you for the helpful suggestion. The captions of Figures 7 and 10 have been revised and reformatted to ensure consistency with the formatting style used for all figures throughout the manuscript. (See Page 8, Line 228-229; Page 14, Line 403).

Comments 9: Some key viewpoints lack literature support, such as "The food industry consumes about 30% of the energy used worldwide, which accounts for 20% of greenhouse gas emissions" in Line 276. It is recommended to supplement the literature support for key viewpoints, verify and revise the literature numbers.

Response 9: Thank you for your valuable comment. The statement has been revised and supported with an appropriate literature reference to improve accuracy and reliability. The sentence has been updated to: “The global food system is highly energy-intensive and is responsible for approximately one-third of global greenhouse gas emissions [49].” The references in this section have also been verified and updated accordingly. (See Page 10, Line 262-263).

Comments 10: Some chemical equations in the article are written incorrectly, such as Fe2O3 in Line 596 and Al2O3 in Line 630. Suggest a comprehensive inspection and modification.

Response 10: Thank you for your valuable comment. The chemical formulas have been carefully reviewed throughout the manuscript, and the notation has been corrected where necessary to ensure proper formatting and consistency. In particular, Fe₂O₃ and Al₂O₃ have been revised using the appropriate subscripts, and similar issues in the manuscript have also been checked and corrected accordingly. (See Page 18, Line 534,539; Page 19, Line 564;).

Comments 11: In the classification section of micro heat exchangers, it is mentioned that they can be classified into conventional channels, mini channels, and micro channels according to size, but the industry standards or sources for this classification are not clear. There is confusion in the definition of the concepts of "micro heat exchangers (MHEs)" and "micro channel heat exchangers (MCHEs)", and some paragraphs mix the two without clearly explaining their inclusion relationship and differences. It is necessary to clarify the definition, classification standards, and sources of core concepts, and clarify the boundaries of easily confused concepts.

Response 11: Thank you for your insightful comment. The section has been revised to clarify the classification criteria and definitions of key terms, and appropriate references have been added for the classification of conventional, mini, and micro channels. In addition, the distinction between micro heat exchangers (MHXs) and microchannel heat exchangers (MCHXs) has been clarified to avoid confusion between these concepts. (See Page 7, Line 177-188).

Comments 12: The English could be improved to more clearly express the research.

Response 12: We thank the reviewer for this suggestion. The manuscript has been carefully reviewed and revised to improve the clarity, readability, and overall quality of the English language. Necessary corrections and refinements have been made throughout the text to ensure that the research is expressed more clearly and professionally.

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

Accept in present form

Author Response

Comments and Suggestions for Authors: Accept in present form

Authors’ Response: Dear Reviewer, thank you for your positive evaluation of our manuscript and for recommending acceptance in its present form. We sincerely appreciate your time and effort in reviewing our work. Your support is highly valued.

Comment 1: The English could be improved to more clearly express the research.

Response 1: We thank the reviewer for this suggestion. The manuscript has been carefully reviewed and revised to improve the clarity, readability, and overall quality of the English language. Necessary corrections and refinements have been made throughout the text to ensure that the research is expressed more clearly and professionally.

Reviewer 3 Report

Comments and Suggestions for Authors

All comments have been addressed, and the manuscript is now clearer and better structured. I recommend its acceptance as it is.

Reviewer 4 Report

Comments and Suggestions for Authors

Review Reports

Reviewer #2: