Design and Optimization of Geometry of Liquid Feed Conveyor Pipes
Round 1
Reviewer 1 Report
Comments and Suggestions for Authors
This research aims to explore the impact of structural parameters of the spiral pipe on liquid feed flow characteristics using the Eulerian two-fluid model, to overcome insufficiently stable liquid feeding delivery. Findings reveal a substantial enhancement in slurry homogeneity during transit through the spiral pipe compared to conventional straight pipe configurations. These results offer valuable insights for the design optimization of liquid feed conveyance systems. However, it has some minor flaws commented below:
· Pressure is discretized in second-order format, while the first-order windward format was used, can the reasons for choosing these formats be explained?
· Table 1 should have explanation how structural parameters (number of guide vanes, angle, length, height) of different spiral pipes are selected. Please cite the articles accordingly, if the scientific articles were involved in making the decision about selecting parameters.
· Table 2 contains simulations parameters, please explain or cite research, how it is measured or selected diameter od 75 µm of solid phase and velocity inlet of 3 m/s.
· The selection of mesh is well explained, since it is of crucial importance that the selected mesh is reliable and convenient for the simulation model. The only missing result is the approximate computational time of the simulations. Please state the approximate computational time of the simulations.
· Please define parameter dp in Equation (9).
· Lines 208-210: “As shown in Figure 5, the calculated concentration distribution is more consistent with the original experimental results, suggesting that the simulation model is relatively reliable.” The Figure 5 present dependance of position on volume fraction for different concentration and volume rates and the comparison between experiments from cited research and simulation from this research. Figure 5 shows relatively high simulation accuracy, although, presenting Figure 5 without numerical/statistical confirmation is not enough. It is strongly suggested to calculate the error of the simulation relative to presented experimental research and include this kind of simulation verification in the manuscript.
· Lines 286-290: “Take 250 cross sections perpendicular to the axis at equal intervals between 40D and 90D of the test pipe. Sampling points are set on the interface and the coefficient of variation (COV) of the current cross-section is calculated. the smaller the value of COV, the more homogeneous the solid phase distribution on that cross-section. the COV is calculated as follows:” Please rephrase the first sentence and correct the beginning of the second and third sentence, respecting the beginning of the sentence with the capital letter.
Author Response
Please see the attachment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for Authors
The paper numerically investigates the impact of swirl flow on two-phase solid-liquid flow using the Euler-Euler method. I have categorized my comments into two sections: general feedback on the entire study and specific corrections for line and page numbers.
Overall, I believe major revisions are necessary for the paper to meet publication standards.
General Feedback:
1. The introduction lacks specificity and requires more focus on the topic and the objectives of the paper.
2. The paper lacks sufficient references; many key statements lack supporting citations.
3. The English used in the paper is poor and affects readability in certain sections.
4. The novelty of the study is not clearly presented in the introduction.
5. The simulation model and the rationale behind using specific constants need clearer explanations.
6. It has never been mentioned about the flow properties such as Re number in the paper
7. The paper severely lacks of enough scientific arguments
Detailed Feedback:
P1-L13: What is influence law? The sentence needs to be reworded.
P1-l20: The statement about the result of this study is too strong!
P1-L35: The statement about the labor cost has been repeated several times.
P1-L42: Two-phase fluid?
P2-L46-48: Needs references.
P2-L49-51: Needs references.
P2-L54,58,60: Should be capital letter.
P2-L63: “avoid the appearance of moving and stationary bed needs rewording.
P2-L65: Needs references.
P2-L68: “Velocity’ ‘limit”, needs comma.
P2-L78: It is mentioned “Numerous studies”, but you just have one reference. It needs more references!
P2-L78: “The critical velocity of flow for the same slurry in spiral pipes is lower compared to conventional circular pipes” needs references.
P2-L83-85: Needs to be reworded.
P2-L89: “Due to the high cost and complexity” needs to go to the next paragraph.
P2-L95: Do you mean CFD-DEM?!
P3-L104-108: Too long sentence. It needs to be reworded.
P3-L114-115: Needs to be reworded.
P4-Table 2: You haven’t explained what is the reason for using these solid particles properties? Does it have any industrial reason?
P4-L139-141:
What is your reference for this statement:
“The Euler-Lagrange method is limited in its applicability to this study due to computational and statistical constraints, particularly when dealing with high-con-centration solid-liquid systems and fine particles.”
P4-L146: What are the reasons for using RNG K-e model in this paper? You haven’t covered it in your paper at all. It also needs references.
P5-L159-160: This statement needs references:
“ The RNG k-ε model can better simulate problems such as separated flow, secondary flow, and spiral flow.”
P5-L167: How did you get to use these values for the constants? Any technical reasons? Otherwise, what are the references for that?
P5-L174: What is the reason for the following statement?
“the use of the Wenyu Drag Model is more appropriate for description.”
P6-L204: Mentioning the statement about using the Schaan’s experimental results could be stated much earlier in the paper.
P8-L221: It has been mentioned that “significant increase in velocity at center” is observed in swirling flow. However, according to the figure 6, that’s not the case in 43D afterwards of the STP where the velocity is higher than SPP. How can you explain this?
P9-Fig 6: I don’t understand why the STP in 42.5D is so different from 42D and 43D. You need to explain this. the flow looks like developing, but then this change is observed here.
P9-Eq 10: It doesn’t look right. Double check it!
P10-L235-239: Are you talking about the outlet of the pipeline or about 45D? its not clear. from the figure what I can see is that all increases happen at 45D which is not the downstream of the flow!
P10-L244-246: You don’t need to use capital letters here!
P10-L244-246: Well right all the parameters are increasing. But what is the point? Where is the optimum point?
P11-L249: Effective doesn’t need to be capital.
P11-L248-251: From what I can see in figure 7, at 80D the swirl number is the same for all conditions. what are you trying to say here?
P11-L253-254: Needs references or more explanations.
P11-L254-257: Too long sentence. Needs to be reworded.
P11-Fig 9: You said the swirl flow has greater pressure drop. Then why the value of Se is not negative?
P11-L264: What do you mean by saying negative correlation?
P11-L264-269: Needs more explanations and scientific arguments.
P11-L269-271: Needs more explanations and scientific arguments.
P12-Fig 10: Is N3 supposed to be A3?
P12-Eg 12: Needs references.
P12-L288: “The smaller” needs to be capital.
P12-L292: What is n?
Comments on the Quality of English Language
The English of the paper is not good and needs to be revised.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
Comments and Suggestions for Authors
Dear Author,
Thank you for addressing the comments. However, there are a few remaining points that I recommend addressing:
-
Comment 5 Response:
- Consider incorporating the response from Comment 5 into the article. It could enhance the overall content.
-
Comment 6 Response:
- I remain unsatisfied with your justification in Comment 6. Since you mention STP, it would be beneficial to discuss the Reynolds number (Re) as well. This additional context would strengthen your argument.
- Comment 8 Response:
It is not in your manuscript. -
Comment 32 Response:
- I still have concerns about Figure 6. It appears that it does not fully adhere to the continuity equation. Please review it carefully.
Thank you, and I look forward to further improvements.
Best regards,
HR
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
