Status, Features, and Future Development of the LIFUS5/Mod4 Experimental Facility Design
Round 1
Reviewer 1 Report
The article is well written and authors explained in detail the objective of the article. I would like to suggest few minor improvement in the article.
1. Abstract section can be improved by writing it more concisely.
2. Introduction section can be improved by adding more recent literature.
3. Conclusion section look like result and discussion & section. Improve the Conclusion section by mentioning only the outcome of the study.
Author Response
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Reviewer 2 Report
A very nice, high quality paper. The only suggestion could be to improve the presentation is to redraw Figure 1. in a higher resolution.
Author Response
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Reviewer 3 Report
In principle, the article describes almost the same technological system that was well described several times already, particularly in cited articles (self-citations actually). I do not consider minor change of your system - disconnecting of sensitive parts with low importance for the measurement, some rearrangement of pipes – to be significant enough for independent article. A very few information about individual parts confirms the perception that it is just reusing of existing system.
I would consider the article as more valuable when the water-to-LiPb injection device will be presented. It is clear that this system is a key component and its new design for application in TBS module can significantly differ from the present LIFUS5/Mod3. You have mentioned that this device is still in design process (lines 259-261). I would expect at least the design requirements or the experienced issues of former version that shall be solved by new design.
According to planned measurements. I understood, you want to use assessment of H2 amount as the main indicator of amount of water that reacts with LiPb. From article cited, it is clear that this measurement takes a long time with risk of measurement error. I recommend at least comparing of this measurement with water level change in the loop of water cooling system.
LOCA has one of the most severe consequences, surely. But, I would prefer to check not only sudden rupture of big pipe, but presence of small leak via cracks in pipe. That could introduce small influx of water that would be hard to detect on the background (particularly with Tritium production (just a heavy Hydrogen). Nonetheless, within the LiPb loop will start to appear LiOH crystals enhancing abrasive and corrosive effects of the liquid metal on the piping. I expect at least effect on lifetime of the LiPb loop components. Do you expect any other system for water leak detection for the long-term operation tests and particularly the operation at reactor (ITER, DEMO, ...)?
Particular questions & comments:
- - There is comparison of pipe length and bending, but not even notice about pipe diameter. This is very important for pressure wave spreading and dumping
- - Figure 3 – you have non-integer count of 90° bends (between valve and TS in both direction), is it a mistake or creative evaluation of piping parameters?
- - Exact number of the bends is one part, but very significant is ratio of pipe diameter and bend radius, is it kept as well?
- - What shall be LiPb circulation speed in most common pipe size? Not the mass flow but really speed of flow. High speed can have influence on pressure wave propagation, particularly on tank inlets/outlets...
- - I would expect, that all the sensors are used for data acquisition and evaluation. I see no reason for using of the data only for control or only for safety system without further utilization (clearly in case of thermocouples).
- Citations are focused on work of your team particularly, I strongly doubt, that nobody else in the world is interested in this topic.
Author Response
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Round 2
Reviewer 3 Report
I would prefer to add more citations of your colleagues from other institutions. Try to add some at least for introduction part...
Rest of my requirements was partly fulfilled and I see that more improvement is hardly possible within reasonable time...
