Review Reports

Round 1

Reviewer 1 Report

The paper ‘Evaluation of Cylindrical Asymmetric Surface Dielectric Barrier Discharge Actuators for Surface Decontamination and Mixing’ deals with the ability of surface DBD to inactivate bacteria. A cylindrical actuator geometry, with different electrode numbers, has been utilized, trying to increase induced flow velocity and mixing. Authors found that, by increasing electrode numbers, a more uniform mixing is achieved and a more effective inactivation of Salmonella enterica is obtained.

It is my opinion that the paper lack of a very important part related with actuators dimensions, material, supply conditions and so on. Which is the voltage utilized. Which is the average power? In which way actuator is scaled when actuator number is increased, by maintain constant the total average power?

In PIV results there are no indications about absolute values. Which are induce velocities?

When treating biolog

The paper ‘Evaluation of Cylindrical Asymmetric Surface Dielectric Barrier Discharge Actuators for Surface Decontamination and Mixing’ deals with the ability of surface DBD to inactivate bacteria. A cylindrical actuator geometry, with different electrode numbers, has been utilized, trying to increase induced flow velocity and mixing. Authors found that, by increasing electrode numbers, a more uniform mixing is achieved and a more effective inactivation of Salmonella enterica is obtained.

It is my opinion that the paper lack of a very important part related with actuators dimensions, material, supply conditions and so on. Which is the voltage utilized. Which is the average power? In which way actuator is scaled when actuator number is increased, by maintain constant the total average power?

In PIV results there are no indications about absolute values. Which are induce velocities?

When treating biological samples, in which way setup is arranged? Which is the diameter of the cylindrical actuator? Which is the diameter of the treated sample?

For these reasons, I suggest to reject the paper.

Author Response

Response to Reviewer 1 Comments

Point 1: The paper lacks important parts related to actuator dimensions, material, supply conditions, and so on. What is the voltage utilized? What is the average power?

Response 1: A new section named ‘Experimental Setup’ has been added after the introduction and before the discussion and analysis that outlines the actuator material and design, the electronics setup, the PIV setup, and the biological experiment setup. The ‘power supply’ of this experiment was a 4.8V battery pack (4 AA).

Point 2: In what way is the actuator scaled when the actuator number is increased? Is it by maintaining constant total average power?

Response 2: At the end of the introduction, there is a short excerpt that explains the power being held constant across all experiments (even with changes in actuators). This causes the individual power sent to each actuator to lower (due to simple voltage laws). The intensity of the plasma lowers as a result, but the overall plasma volume has increased due to the surface area of plasma being formed, albeit weaker.

Point 3: In the PIV results, there are no indications about absolute values. What are the induced velocities?

Response 3: New images have replaced the older analysis images in the ‘Results and Discussion’ section. These images have the absolute values to compare across images.

Point 4: When treating biological samples, in which way is the setup arranged? What is the diameter of the cylindrical actuator? What is the diameter of the treated sample?

Response 4: In the aforementioned newly added ‘Experimental Setup’ section, the biological setup was described, and a schematic was given. The diameter of the actuators varied slightly but were generally around 1” in diameter. The treated samples were small inoculated samples that sat on a coverslip smaller than the 1” diameter of the cylinders.

Reviewer 2 Report

1. The authors do not have an “Experimental set-up” section; please make a section, and insert the conditions of your experiments (power, time treatment, surface scanning or not, etc.), describe the instruments/ software that you are using during the measurements (company name, parameters, resolutions, etc.).
2. Please insert a sketch of your experiment, something that will be easier for the reader to understand your plasma device;
3. In which domain do you use de plasma, in DC, RF, Microwave, etc.? Please specify in the manuscript.
4.  The authors said that they are using air, for the plasma discharge. From where did you inserted the air, from the Ambient atmosphere, or from a controlled air gas tank?
5. What was the air quantity (sccm, or slm, etc.) injected?
6. For Figures 1, 2, 3 and 4: please insert a color scale bar, or something that will show the level of your colors. For example, in Fig 2 d, it can be observed 5 orange levels, or not? What is the lowest level and the highest level? Please insert a color bar along with the values for each color level.
7. Please review the Data Availability Statement; what is written is from the template. Please make corrections.
8. Please review Acknowledgments section; again, what is written is from the template. Please make corrections.

Author Response

Response to Reviewer 2 Comments

 

Point 1: The authors do not have an “Experimental set-up” section; please make a section, and insert the conditions of your experiments (power, time treatment, surface scanning or not, etc.), describe the instruments/ software that you are using during the measurements (company name, parameters, resolutions, etc.).

 

Response 1: An ‘Experimental Setup’ section has been added to clarify various points of the experiment such as actuator materials and design, the PIV setup, and the biological experimental setup.

 

 

Point 2: Please insert a sketch of your experiment, something that will be easier for the reader to understand your plasma device.

 

Response 2: In the newly added ‘Experimental Setup’ section, a schematic has been added for both the PIV experiment and the biological experiment.

 

Point 3: In which domain do you use de plasma, in DC, RF, Microwave, etc.? Please specify in the manuscript.

 

Response 3: We’ve clarified a bit more in the newly added ‘Experimental Setup’ section that the actuator will receive a high voltage AC current. Additionally, the specifications for the transformer have been given to help elucidate output results.

 

Point 4: The authors said that they are using air, for the plasma discharge. From where did you inserted the air, from the Ambient atmosphere, or from a controlled air gas tank?

 

Response 4: The air used for the experiment was ambient air. A statement specifically addressing this was added to the end of the first paragraph in the ‘Experimental Setup’ section.

 

Point 5. What was the air quantity (sccm, or slm, etc.) injected?

 

Response 5: This has been addressed in the previous response. There was no air injected. The air used was simply ambient air with a fog generator used to seed the air for PIV measurements.

 

Point 6. For Figures 1, 2, 3 and 4: please insert a color scale bar, or something that will show the level of your colors. For example, in Fig 2 d, it can be observed 5 orange levels, or not? What is the lowest level and the highest level? Please insert a color bar along with the values for each color level.

 

Response 6: Great suggestion. This has been added to analysis figures.

 

Point 7. Please review the Data Availability Statement; what is written is from the template. Please make corrections.

 

Response 7: This has been addressed and changed.

 

Point 8. Please review Acknowledgments section; again, what is written is from the template. Please make corrections.

 

Response 8: This has been addressed and changed.

Round 2

Reviewer 1 Report

The manuscript can be now accepted by the Journal.

Please carefully check english.

Reviewer 2 Report

The authors made the changes inside the manuscript according to reviewer's comments/ suggestions. The manuscript can be accepted for publication.