A SAR Micromixer for Water-Water Mixing: Design, Optimization, and Analysis
Round 1
Reviewer 1 Report
The paper can be considered for publication, but only after the below remarks are answered/addressed point-by-point:
-Throughout the complete paper there are "Error! Reference source not found", this is rather sloppy and should have been solved by the authors before submitting.
-some spaces are missing in the keywords and between keywords.
-The introduction is rather poor as there is no clear indication of the "gap" and also a structure overview of the paper is missing.
-line 119 is again an example of very confusing because spaces are missing! This must be fixed throughout the complete paper.
-Equation1: definition of d is not given?
-I find the sentence (line 157) "Uniform Quad and Tri meshes were created by applying the sweep method with no suppression condition." rather cryptic.
-The information at section 3 is insufficient. There is no drawing of the computational domain, the boundary conditions are not given, the inflow condition is also not provided. Furthermore, the information of the mesh is insufficient to reconstruct it. As such, the reader has no idea about the quality of the results (or could not reproduce your results at all).
-What I question is (maybe i over-read it): what is the initial distribution of the two species?
-Figure 4: the font size is too small (this applies also to the other figure up to (and including) figure 12.
-Figure 5: Error bars should be given. The authors should try to get this from the experiments.
-Figure 6: It should be mentioned what is the meaning of the colours.
-Figure 8: the vectors can not be seen at all. This figure must be improved a lot! Also, the plane which it is evaluated is unclear to me. Maybe a small schematic would help.
-In general, the following References are missing and must be added:
Lee et al, A split and recombination micromixer fabricated in a PDMS three-dimensional structure, Journal of Micromechanics and Microengineering, 2006.
Capretto et al, Micromixing within microfluidic devices, Microfluidics, 2011.
Nguyen and Wu, Micromixers - a review, Journal of Micromechanics and Microengineering, 2004.
Kim et al, A barrier embedded chaotic micromixer, Journal of Micromechanics and Microengineering, 2014.
Wang, Liquid Mixing Based on Electrokinetic Vortices Generated in a T-Type Microchannel, Micromachines, 2021.
Lee at al, Microfluidic mixing: a review, International journal of molecular sciences, 2011.
Lu et al, A magnetic microstirrer and array for microfluidic mixing, Journal of Microelectromechanical Systems, 2002.
Author Response
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Author Response.docx
Reviewer 2 Report
This manuscript proposes a new split and recombine micromixer and numerically investigates its mixing performance. The parameter of connecting angle ? is studied and discussed in detail. The results show that the micromixer has a maximum efficiency when the value of ? is 45°. The results may have some potential impact in the field of microfluidics. My other comments for this work are as follows:
(1) When the value of ? is 45°, vortices form in the microchannel (Figure 8), resulting in better mixing efficiency. Why is there no obvious vortex formed in the microchannel under other values of ?? The author should give a more in-depth explanation of the results in Figure 7.
(2) The results in Figure 9 are predictable. I do not think it is necessary to discuss it.
(3) What is Figure 11 added to the manuscript to illustrate?
(4) Since the H-C micromixer and the (Y-U)? micromixer have different lengths and depths, I do not think it is very reasonable to compare with each other directly (Figure 11 and Figure 12). The H-C micromixer should be scaled equally to the same length and depth as the (Y-U)? micromixer, then compared with each other, which may be more reasonable.
(5) Maybe Figure 1, Figure 2, and Figure 3 are screenshots in the software. In these figures, the colors of the channel and the background are a little similar. It's best to remove the background color.
(6) In practical application, the fabrication of such a complicated microchannel may be a challenge. How to solve this problem?
(7) The manuscript has many format errors and citation errors, such as Line 97, 100, 110, and so on. Some words are written incorrectly (e.g., “angel” in Line 96 and “perfroming” in Line 152). The author should carefully check the manuscript before submission.
Author Response
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Round 2
Reviewer 1 Report
The authors have implemented my remarks sufficiently. However, I do feel the authors should try to improve the quality of the figures as they seem of a very bad resolution (in comparison with the previous version the authors just up-scaled the figures, without improving the resolution, leading to these pixelated-figures). After the improvement of the figures the paper can be accepted.
Author Response
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Reviewer 2 Report
(1) “The comparison of mixing efficiency between the ′H − C′ and the ′(Y − U)?′ micromixers changing the angle ? under varying Reynolds numbers is presented in Figure 8.”—Line 230 and 231. However, Figure 8 does not show the mixing efficiency of the ′H − C′ micromixer.
(2) Since it is very easy to understand the influence of Re, and the point of the work is the influence of the angle ?, it is best to display the variation of mixing efficiency with the angle ? under several Reynolds numbers in Figure 8, then one can easily see the effect of the angle ? on the mixing efficiency. In addition, the authors can add more angle values to show a more detailed variation trend of mixing efficiency with the angle.
(3) “Efficiency decreases if the value of ? deviates from 45°.”—Line 238. However, the mixing efficiency for 75° is larger than that for 60° (see Figure 8). Why? If Figure 8 is modified following comment (2), one can see the variation trend of mixing efficiency with the angle ? likes an M-shape, which is not fully explained. In Figure 12, the variation trend of mixing effectiveness with the angle ? also likes an M-shape. These phenomena should be given a reasonable explanation.
Author Response
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