Single/Multi-Objective Optimization Design and Numerical Studies for Lead-to-Supercritical Carbon Dioxide Heat Exchanger Based on Genetic Algorithm
Round 1
Reviewer 1 Report
The manuscript is well written, the bibliography is relevant, and it is well structured.
Equation 5 should be explained in detail, in particular the constants C1 and C2, and equation 1 should be referenced.
Figure 2 should be explained in detail.
Is equation (16) correct? You should also reference it
After applying the genetic algorithm, you should compare the original design with this one.
The performance of the heat exchanger must be calculated explicitly as the ratio of the thermal power and the mechanical power, in addition to evaluating the irreversibility, it must use entropy differences in the base cases and the optimized case.
In the numerical results, you must report the mechanical and thermal power of the heat exchanger and compare it with what is obtained analytically. How much do they differ?
Despite the results presented, it is not shown that the heat exchanger obtained is optimal and with what criteria this could be determined.
Author Response
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Author Response File: 
Author Response.docx
Reviewer 2 Report
Single and multi-objective optimization based on genetic algorithm was applied to optimize the design for the primary heat exchanger (HE) in lead-cooled fast reactor (LFR), where liquid lead and supercritical carbon dioxide (SCO2) are the working fluids on hot-side and cold-side of HE, respectively.
Comments
The paper is of great practical significance. Please complete the literature review with the following two references:
[R1] Taler D., Semi-empirical heat transfer correlations for turbulent tube flow of liquid metals. International Journal of Numerical Methods for Heat and Fluid Flow, 2018, Vol. 28. No.1, pp.151-172.
[R2] Taler D., A new heat transfer correlation for transition and turbulent fluid flow in tubes. International Journal of Thermal Sciences, 2016, Vol. 108, pp.108-122.
Reference [R1] proposes several correlations for calculating the Nusselt number on the inner surfaces of pipes in liquid metal flow for different models describing the turbulent Prandtl number. The correlations proposed in [R1] can be applied when liquid metal flows inside the exchanger tubes.
In reference [R2], a correlation is derived for the calculation of the Nusselt number in pipes for transition and turbulent flow in the range of Reynolds numbers from 2,300 to 1,000,000. The correlation (6) used in the reviewed paper is suitable for turbulent flow when the Reynolds number varies from 4,000 to 500,000 (and not from 2,300 to 500,000 as the authors reported).
Author Response
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Author Response File: Author Response.docx
Round 2
Reviewer 2 Report
1) Cite the reference from which equation (20) was taken.
2) Whether in formula (23) the denominator should be raised to the power of 1/3? (please consult the book of R.L. Webb, Principles of Enhanced Heat Transfer -2nd Edition).
Author Response
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Author Response File: Author Response.docx
