Beam Transmission (BTR) Software for Efficient Neutral Beam Injector Design and Tokamak Operation
Round 1
Reviewer 1 Report
The BTR code is a widely-used and much-loved package for simulation of neutral beam injectors for nuclear fusion devices. The physics and applications of the code have been well described elsewhere, most recently in the Symposium on Negative Ion Beams and Sources, refs 9-11 in the manuscript. However, the code and code interface itself has not been described in the same appropriate detail outside the web location (ref. 1 in the manuscript). Therefore the present publication is most welcome.
I endorse the choice of MDPI Software for this article. The alternative Computer Physics Communications is not really suitable; it publishes a lot of fusion-relevant work, but much more on the side of basic rather than applied physics. Reviews of Scientific Instruments comes to mind briefly, but it is not suitable for such detailed description of software. MDPI Software is a good choice.
The paper is clear and complete and I do not have technical criticisms. I recommend the paper for publication in Software.
Author Response
Dear Reviewer,
Thank you very much for your kind endorsement of the paper.
Hopefully it can be really useful for BTR users.
authors
Reviewer 2 Report
Referee report on the manuscript
“Beam Transmission (BTR) software for efficient neutral beam injector design and tokamak operation“, by Eugenia Dlougach, and Margarita Kichik
General:
The BTR code has being used worldwide was originally developed and used to design the Neutral Beam Injection (NBI) system for ITER. The version described here is the extension of the original BTR code enabling solution of the tasks which include the NBI interaction with tokamak plasmas. The description includes the detailed physics of modelled processes, methods used, user interfaces and examples of application of extended version to assessment of the NBI shine-through loss for designs of DEMO-FNS and FNS-ST tokamaks.
The information published in the manuscript looks very useful for the BTR users worldwide.
The publication of the manuscript in the Journal will provide the legal reference for the users. Thus, I would recommend to publish the manuscript after some editorial changes (see comments below)
Detailed comments:
1) abstract
I would suggest to modify the abstract following the criteria that:
1) Should contain brief description of the content;
2) Should not contain the references;
3) Should not interfere with the Introduction (there are duplications in present version).
Suggestion:
To replace the abstract by something like the first paragraph of “General” (see above)
2) Lines 28-35
Comment:
The text of the manuscript up to “While …” in the line 35 practically duplicate the beginning of the next section.
Suggestion:
Remove the whole text from the Introduction, and replace it by something like:
The beam transmission line is the inherent part of the NBI systems (see Section 2.).
3) Line 41
Written:
injector surfaces
Suggestion:
beam facing surfaces
4) Line 41
Written:
next
Suggestion:
further
5) Line 47
Written:
changed
Suggestion:
is changed
6) Line 55
Written:
is burnt
Suggestion:
is damaged
7) Line 63
Written:
began
Suggestion:
started
8) Line 66:
Written: ~2005
Suggestion: 2005
Comment: please specify accurately or eliminate
9) Line 69 (2 times):
Written:
ITER
Suggestion:
the ITER
10) Line 75
Written:
~ 20
Suggestion:
20
11) Line 101
Written:
thermonuclear plasma heating
Suggestion:
plasma heating
Comment:
Not only thermonuclear plasma. It works well also for hydrogen and He plasmas.
Contribution of the NBI in nuclear power production is rather moderate in the reactor scale plasmas such as ITER.
12) Line 102
Written:
nuclear fusion devices like
Suggestion:
devises with magnetic plasma confinement, such as
Comment: see comment to line 101
13) Line 104
Written:
the target machine by and
Suggestion:
each machine and
14) Line 105-106
Written: “main source of high-energy particles”
Suggestion: “main external source of high-energy particles and torque”
Comment: for future fusion reactors these are fusion reactions, in present machines all heating methods create population of fast particles which heat the thermal bulk.
15) Lines 106
Written: “steady-state ‘beam-driven’ scenarios”
Suggestion:
To specify what does it mean exactly? “Steady-state” is reserved for full non-inductive current drive (in the sense that it does not consume the magnetic flux). In all cases there is intrinsic bootstrap current. Do you mean fully non-inductive current with dominant NBCD?
16) Line 114:
Written:
tokamaks; they include
Suggestion:
tokamaks including
17) Line 134:
Written:
hydrogen (or deuterium)
Suggestion:
To remove the statement.
Comment:
Up to now the NBI was carried out for H,D,T,He elements.
18) Line 139:
large plasma devices (with R > 2 m) only negative-based
Suggestion:
reactor-scale devices require the energies of the MeV scale, which is possible only for the negative-ion-based
Comment:
JET has the major radius of R=3m and NBI based on the positive ion sources.
19) Line 141-142:
Written:
burn the opposite wall (‘first wall’, or FW)
Suggestion:
damage the beam facing surfaces
Comment:
Typically the FW is protected by shielding blocks to withstand the NBI load
20) Line 147:
Written:
typically features several channels design
Suggestion:
typically has multi- channel design
21) Line 150-152:
Written:
Therefore, for 150 large fusion devices (e.g. tokamaks with R > 2 m), where neutral beam energy (Eb) is
above 70 keV per nucleon (or 70 keV/amu), only negative-based neutral beams can be 152 efficiently produced,
Suggestion:
To remove the statement (see comment to line 139 above)
22) Line 505 (+ line 951)
Suggestion: to remove reference [34]. It is not a good style to refer to the textbooks, rather than the original papers, but in this very case the statement in the manuscript is trivial and does not require a reference.
23) Line 592:
Written:
beam ionization in plasma
Suggestion:
beam ionization and charge-exchange with thermal ions in plasma
24) Line 606-613:
Note, that formulas by Janev are valid above 60keV/amu.
25) Line 761:
Written:
Duct
Suggestion:
duct
26) Line 881
Suggestion: to replace “Beginning” by “Starting”
27) Conclusions and outlook
General
There is a special format of the DB and interfaces adopted for ITER, IMAS [Nucl. Fusion 55 (2015) 123006 (13pp) doi:10.1088/0029-5515/55/12/123006]
It would be useful to mention whether the authors are going to adopt the BTR software to LINUX machines and make it IMAS compatible.
28) References:
General suggestion:
To unify format of the references following the standards of the Journal and delete the references mentioned above.
Author Response
Dear Reviewer,
Thank you very much for your high opinion and detailed comments.
We corrected the paper according to all your suggestions, removed and rewrote some fragments.
Sincerely yours,
authors
Reviewer 3 Report
This manuscript has introduced the development history of software of BTR, which is abbreviation of Beam Transmission Ratio for neutralization beam injector design, the authors like to call it as ‘Born To Run’, which means the software is suitable for the user to design the related NBI. The authors give a lot of figures to show the designed results for the given example and the agreements between BTR and SAMANTHA, prove the reliability of BTR. This software has a very good prospects, so it is very useful for the society to let more users to use this software to promote the FNS great progress.
The only regret for the authors, they may prepare all the figures to be sure every figure has the suitable coordinate variables with the right unit, such as figure 2, lack of the dimensions and unit of m; Figure 3, lack of the units of X, Y and Z; Figure 4ab, Figure 5, Figure 7,Figure 8,Figure 10,Figure 11,lack of units
Figure 9, E+20, E-02, not right format for the publication, should be 10^20, 10^(-2);Fiigure 10, Figure 14,Figure 15,Figure 16,the same problem with figure 9,
Figure 13abcd ,Figure 18, not clear, especially for the coordinates.
Almost every figure need to be redrew to use same text size and make it clear to be read and to use the scientific counts format 10^7 not 1E7.
/
Author Response
Dear Reviewer,
Thank you very much for your response and important suggestions.
We tried to improve the figures where it was possible. However, the units in original BTR plots (which are part of BTR graphics) are kept as they are shown on BTR screen. This is not a scientific notation (the format you proposed is not scientific too - TRUE scientific would be m × 10n), but the figures in the paper are intended to show BTR graphics as it is.
Thank you again for BTR usage,
authors
Round 2
Reviewer 3 Report
The authors have done their great efforts to try to modify every figures to fit the requirements of publication. I understand it is very difficult to correct the data format in the output figures of the running software. But it is still the problem, it is also general problem by the computer software. It can only output the data with format of E+(or-) a number. The editor could make a decision to let it exist in the manuscript. Normally it isn’t allowed.
The other questions are well solved and modified one by one by the authors.
I think it can be accept by the software.
