Achieving Zero-Impact Emissions with a Gasoline Passenger Car

Round 1

Reviewer 1 Report

-     INTRODUCTION – The introduction section is not presented well and needs to be improved. What's the importance of your research?  In what way does this research provide novel insights? What’s the contribution of your study?

-  CONTRIBUTION – Could you please clarify what is the contribution of your study? What’s the policy implementation of your research?

In lines 50 and 53, you mentioned that "There is however no research yet, evaluating complete system designs for Euro 7 and Zero-Impact under the most challenging boundary conditions. Therefore, a holistic approach is chosen in this paper to evaluate possible solutions for future emission reduction". There are many studies in the concept of your research. You need to explain your aim of this research. What is the significance of this research? It is important to explain why you chose this topic, and what insight you will bring to the market. 

-  LITERATURE REVIEW – There is no review of previous studies in this paper, neither in the introduction nor in the literature review sections. It is important to review previous studies and explain how your research will fill the gap.

-     Figure 2 is not presented in the manuscript.

-   Page 6, lines 185-186, you mentioned that “Trend curves are generated based on various analyzed datasets as depicted in Figure 5, to derive the vehicle parameters for 2030 assuming steady development”. You need to explain dataset and analyses applied to create trend curves. How did curves get created?

-  Page 7, lines 239-243, You mentioned there are various possible scenarios, while you selected four possible cases. Please explain scenarios and specify references if you followed previse studies. How did you find four cases? What made you choose these four cases out of a variety of possible scenarios?

-     Reference – There are 45 references in your study, of which 10 are your own. Even if all these studies are relevant, it is not professional to just cite your previous research. There is no literature review in this study, and this section needs to be improved. In the field of your research, there are many studies (excluding your previous studies) that must be taken into consideration when reviewing the literature.

 

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

The authors proposed the technologies that can be used in gasoline passenger cars to meet near-zero emission standards. Overall, the paper is well writing. The authors are advised to consider the following suggestions to further improve the paper quality.

(1) Lumped references are suggested to be avoided.

(2) The authors are advised to add the description of the paper layout at the end of Introduction section.

(3) Some of the statements in the paper can be supported by existing studies. For example, in line 211, “The maximum altitude is 1600 m – 2200 m” can be supported by Fuel, 2022; 324: 124824.

(4) Figure 2 is missing.

(5) The authors applied TWC (three-way-catalyst modeling) to the gasoline passenger cars. In this paper, the authors need to mention that when the engine is running at Lambda=1, TWC has high efficiency and can reduce CO, NOx and HC simultaneously. This statement can be supported by Journal of Energy Resources Technology, 2023; 145(1): 012302.

(6) In line 125-126, the authors mentioned NH3 and N2O emissions from the aftertreament. It is likely the SCR can produce NH3 and N2O because SCR applies NH3 to reduce NOx. I do not think TWC can have NH3 and N2O emissions. Could the authors please recheck it? In addition, GPF is used for gasoline direct injection engines which have soot emissions. The authors are advised to mention it.

(7) In line 160, “1/min” means “r/min”?

Overall, the paper is well written. The reviewer strongly suggests to accept this paper with minor modifications!

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Thanks for considering all recommended comments. This version of your study is significantly improves. 

However, I am still worried about literature and references. Again, 13 studies out of 67 references are related to the the authors of this paper. Its not professional to just re-reference your previous studies. maximum 4 or 5 papers is acceptable, not 13 studies. This shows that previous literature cannot support the significance and acceptability of your research.

Author Response

Thank you for the reply. I have added some insights on the sources from our own:

 

• First, we referenced our orignal publication from 2020, where the first demonstrator in the literature explicitly for Zero-Impact Emission was introduced and figure 2 originates from:

 

1. Maurer, R.; Yadla, S.K.; Balazs, A.; Thewes, M.; Walter, V.; Uhlmann, T. Designing Zero Impact Emission Vehicle Concepts. In Experten-Forum Powertrain: Ladungswechsel und Emissionierung 2020; Liebl, J., Ed.; Springer Berlin Heidelberg: Berlin, Heidelberg, 2021; pp 75–116, ISBN 978-3-662-63523-0.

 

• Next, this paper represents a portion of the results that were achieved in a 2 year research project with the FVV eV (Final report ~120 pages), we referenced:
•  
1. the previous publication at Elsevier that builds the basics for this follow up paper
   
   (Maurer, R.; Kossioris, T.; Hausberger, S.; Toenges-Schuller, N.; Sterlepper, S.; Günther, M.; Pischinger, S. How to define and achieve Zero-Impact Emissions in road transport? Transportation Research Part D: Transport and Environment 2023, doi:10.1016/j.trd.2023.103619.)
   
    
2. the corresponding data of the driving cycles
   
   (Kossioris, T.; Maurer, R. Zero-Impact Tailpipe Emissions - Test Cycles, Mendeley Data, V1, doi: 10.17632/z4kdp3k6dp.1. )
3. The methodology for developing the driving cycles
   
   ( Kexel, J.; Müller, J.; Günther, M.; Pischinger, S.; Sens, M. HyFlex-ICE Intermediate Report, 2022.)
    
4. The data for the 2030+ vehicle, that was provided in the project by a industry partner (FEV Europe GmbH) and therefore needs reference:
   
   (Uhlmann, T.; Alt, N.; Thewes, M.; Lückmann, D.; Balazs, A.; Maurer, R.; Sahr, C.; Kürten, C.; Vosshall, T.; Müller, A. Hybrid BEV – A One Platform Solution for Future Passenger Cars. In 30. Aachen Colloquium Sustainable Mobility, 2021, ISBN 978-3-00-068207-0.)
    
5. and the final report for full details
   
   (Maurer, R.; Kossioris, T.; Sterlepper, S.; Günther, M.; Bunar, F. Zero-Impact Tailpipe Emissions: Final Report, Project no. 1412, FVV eV, 2023.)
    
6. Since we used the methods that were set-up by a partner working group, we have used this sources:

 

Claßen, J.; Krysmon, S.; Dorscheidt, F.; Sterlepper, S.; Pischinger, S. Real Driving Emission Calibration—Review of Current Validation Methods against the Background of Future Emission Legislation. Applied Sciences 2021, 11, 5429, doi:10.3390/app11125429.

 

• We see these publications as mandatory, since know-how and methods are used in this paper that originate there.

 

• To reduce the amount of references that relate to authors, I have replaced the following 6 references where co-authors were included: 

 

1. Dorscheidt, F.; Sterlepper, S.; Görgen, M.; Nijs, M.; Claßen, J.; Maurer, R.; Yadla, S.K.; Pischinger, S.; Krysmon, S.; Abdelkader, A. Gasoline Particulate Filter Characterization Focusing on the Filtration Efficiency of Nano-Particulates Down to 10 nm. In SAE Technical Paper Series. SAE Powertrains, Fuels & Lubricants Meeting, 2020.
2. Claßen, J.; Pischinger, S.; Krysmon, S.; Sterlepper, S.; Dorscheidt, F.; Doucet, M.; Reuber, C.; Görgen, M.; Scharf, J.; Nijs, M.; et al. Statistically supported real driving emission calibration: Using cycle generation to provide vehicle-specific and statistically representative test scenarios for Euro 7. International Journal of Engine Research 2020, 21, 1783–1799,
3. Thewes, M.; Balazs, A.; Yadla, S.; Walter, V.; Görgen, M.; Scharf, J.; Sterlepper, S.; Voßhall, T. Zero-Impact Combustion Engine. Aachen, Germany, 2019.

1. Pischinger, S. Future perspective of the internal combustion engine, 2020.
2. Menne, C.; Recker, P.; Balazs, A.; Schaub, J.; Ehrly, M.; Maurer, R.; Lindemann, B.; Maurer, B., Dohse, D.; Wilkes, T.; Simons, O.; et al. Advanced Hardware, Controls and Calibration Solutions to Meet the Upcoming EURO 7 Legislation. In 31st Aachen Colloquium Sustainable Mobility 2022, 2022, ISBN 978-3-00-072524-1.
3. Sterlepper, S.; Claßen, J.; Pischinger, S.; Schernus, C.; Görgen, M.; Cox, J.; Nijs, M.; Scharf, J.; Rose, D.; Boger, T. Analysis of the Emission Conversion Performance of Gasoline Particulate Filters Over Lifetime. In SAE Technical Paper Series. 14th International Conference on Engines & Vehicles, SEP. 15, 2019; SAE International400 Commonwealth Drive, Warrendale, PA, United States, 2019.

Reviewer 2 Report

The authors improved the paper quality based on the reviewer's comments.

The paper can be accepted as it is.

Author Response

Thank you.