Dynamic Thermal Neutron Radiography for Filling Process Analysis and CFD Model Validation of Visco-Dampers

Round 1

Reviewer 1 Report

The filling process was studied using experimental and numerical methods by the authors of the paper machines-2336238, titled "Dynamic Thermal Neutron Radiography for Filling Process Analysis and CFD Model Validation of Visco-Dampers." They also used a small-sized visco-damper to quantify the effect of the bearing cut-off position on the filling process length. With the use of the experimental data, they verified the numerical results. They visually and quantitatively assessed the spatial oil spread formation, oil layer patterns, and fluid front velocity values using measurement and modeling. The article is technically sound and accepted due to its excellent writing and presentation. I suggest that this paper be published in its existing form.

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

The paper is interesting, especially by using of non-typical method (neutron radiography) to validate the CFD model.  The methodology is almost correct and well described.    The major weakness of the research is lack of thermal measurements.

The model is claimed to be also thermal, but in experiment the temperature of the damper was not measured so the thermal part of the model was NOT validated.

If the CFD model is intended to check the temperature field (degradation of the oil), the model (thermal part) cannot be considered as validated. It must be clearly pointed out and discussed.  

Detailed remarks: References 1-3 are not related to the topic, and should be removed.

Line 128: If the filling process is done under pressure 10-30 bar after vacuum is developed, that is a pressure at closing? Is it high (10-30 bar), atmospheric (1 bara) or vacuum (0 bara)? It should be clarified.  

L130: The welding process itself can overheat the oil. Was it investigated?  

L217: " free neutrons can only be produced at a working nuclear reactor or accelerator [18, 19]." It is just not true. See for example ESS facility (under construction in Lund (The European Spallation Source) the world’s most powerful neutron source.  

L276 alloy 6060 has different thermal properties, how does it influence the temperature field during  the filling process?  

L330: The table with properties of  Wacker AK 1 000 000 STAB should be provided.  

Fig. 6. A type of pressure sensors should be provided. It is important, because it should be probably also radiation resistant. Also the used camera type should be described.  

Line 420-443: Description of well-known method as CFD is not necessary, it is enough to put some references. Should be removed.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf