Asymmetric Method of Heat Transfer Intensification in Radial Channels of Gas Turbine Blades

Round 1

Reviewer 1 Report

 

Reviewer’s comments on, “Research and development of novel heat transfer augmentation method for high-temperature gas turbine blades (Manuscript ID: inventions-1867905)”

                                                                                                                   

RECOMMENDATION:  POSSIBLE REJECTION:  The manuscript is similar to the article already published elsewhere mentioned

Recommendation OR POSSIBLE REJECTION:

The  manuscript submitted by the Authors is similar to the  article published  elsewhere “  Shevchenko, I.V., Rogalev, A.N., Garanin, I.V., Vegera, A.N. and Kindra, V.O., 2017, October. Research and development of asymmetrical heat transfer augmentation method in radial channels of blades for high temperature gas turbines. In Journal of Physics: Conference Series (Vol. 891, No. 1, p. 012142). IOP Publishing.”

 

Abstract

The Abstract needs a major revision. The grammatical construction of the Abstract is very poor and the contents the abstract viz. precise problem statement & novelty, Aim/Objectives, Methodology Outcome of finding/results, conclusion, prospect applications are not highlighted

“To ensure reliable operation of heat-stressed parts of these tur-bine plants cooling systems are used.” Is unclear

“This paper shows the results for research of asym-metrical method of heat exchange augmentation in the radial channels, which can be used on the blades with a pass or half-pass cooling system. “ need revision

 

The texts “It was established that ar-rangement of near-the-wall holes in the baffle separating the radial channels allows increasing heat removal from the blade surface and reducing temperature non-uniformity between the wall and the pressure side as a result of reducing a boundary layer thickness in one radial channel and creating additional jet-type aug-mentation in other radial channel. By using calculation and experiment approach, it was established that the use of the proposed method of asymmetrical augmentation within the range of Reynolds numbers of 6000 to 18000 ensures average increase of heat loss up to 20% from the backside and 35% from the pressure side of the gas turbine blade feather.”  Are wrongly positioned, wordy and unclear

The entire content and structure of the Abstract need to be carefully re-written

 

1. Introduction: The introductory aspect of the manuscript contains lot of grammatical errors.

The texts, “The threshold of gas temperate increase at the gas turbine inlet is limited by thermal strength of critical parts and assemblies.” Need to be revised

 

The texts, “The best global samples of nickel-based high alloys (with Ni content of at least 70%) have a melting point at the level of 1100-1200°С.” Are poorly expressed

The texts, “To ensure per-formance capa-bility of the parts under such conditions cooling systems that allow reduc-ing an average temperature of the part wall and thus preventing its damage caused by temperature im-pact are widely used.” Are wordy and unclear expression

 

The texs, “It is customary to classify few main areas in the gas turbine blade structure: leading edge, feather midpoint and tailing edge, which are subject to different thermal loads dur-ing op-eration and have their own geometrical limitations.” Need  a revision”

 

Revise,” To augment heat exchange processes in the blade feather midpoint fins are often in-stalled, the use of which allows increasing the heat exchange surface area and additionally swirl the flow by periodical boundary layer separation.”

 

Texts under, “2. Materials and Methods’ 2.1. Research object” need to be revised as they are properly expressed grammatically.

 

Sub-title, “Figure 1. Design of convectional system for cooling the gas turbine blade with asymmetrical flow of the cooling agent in radial channels of the feather midpoint.” Need to be revised

 

The texts, “The channel from which the cooling agent boundary layer is blown-off is called a distribution channel, the channel adjacent to it – a collecting channel. The holes through which a part of the flow is blown-off are located upstream the fins in distribution channel and downstream the fins in the collecting channel. Arrangement of the cooling agent over-flow from the distribution channel to the collecting one allows increasing heat re-moval both from the side of distribution channel by means of reduction of the boundary layer thickness and its thermal resistance accordingly, and from the side of the collecting chan-nel by means of the cooling agent blow-in to the fins “blind” zone, that is character-ized with a low heat loss coefficient.” Need to be revised

The Authors need to re-check and effect correction on the value of Table 1 (see Snapshot)

 

 

 

 

Texts, “The studied channel thermal and hydraulic characteristics…………fact that further tests will be carried out on the test bench with the use of liquid metal thermostat..” In , “2.2. Numerical simulation” method” need to be revised

 

Texts “Results of numerical simulation were processed as follows. The finned surface of each channel was divided into local areas of equal length; rounding areas at the channel angles were cut.” Need to be revised

Texts, “After construction of geometrical surfaces, it is possible to proceed with determina-tion of heat loss coefficient αi, which is determined in accordance with (1).”    Need to be revised. “(1)” need to be checked and corrected. “(1)” needs to be changed to   “Equation (1)”

Texts, “An average temperature of the liquid is calculated from the function (2).” Need to be revised.

 

2.3. Experimental method

Texts, “To study models of cooling channels….The holes are located from the side of the wall that simulates the blade wall from the pressure side.” Need to be revised

 

Texts, “Each thermal diagram (zinc skin) obtained was checked by heat balance according to (12).” Need to be revised.

“(12)”  needs to be changed to   “Equation (12)”  or  “equation (12)” 

 

The Authors need to effect correction on , “Difference in the heat balance did not exceed 5%.” To    “The difference in the heat balance did not exceed 5%.”

 

“Figure 4. Layout of reference sections in which heat flow density was determined.”  Need to be corrected and changed   to    “Figure 4. Schematic set-up of   the reference sections in which heat flow density”

 

Texts under, “3. Results and Discussion” need to be revised.

 

The title “Table 2. Thermal and hydraulic parameters of models studied.” Need to be revised and changed to   ““Table 2. Models for the thermal and hydraulic parameters investigated”  Also, the values : IP; IS; OP; OS; IP; IS; OP; OS need to be checked and changed where possible.

 

 

The Authors need to  check and properly insert correct value in, “Table 3. Asymmetrical heat transfer rates.”  The use of “,” in place of  “.” Is not justified.  For instance , “1,25” cannot be used in place of “1.25”;   “1,18” cannot be used in place of “1.18” etc and for other values in other Tables.

 

“Figure 7. Distribution of Re numbers lengthwise of the channels, case 4.” Need to be revised

The Authors need to revise, “The obtained results of the experimental study of the radial channel model with asymmetrical arrangement of heat removal confirmed efficiency of the developed method of convectional cooling in the radial channels of the blade feather midpoint. Based on re-sults of numerical and experimental studies criterial dependencies were created to calcu-late average heat loss coefficients in the radial channels with asymmetrical heat exchange augmentation.”

“To calculate the thermal characteristic in the radial channels of the blade feather midpoint from the pressure side, the criterial equation is given by (14) and from the blade back side – (15).” Need to be revised.

The Authors need to change “by (14)”     To   “by Equation (14)”    

 

REVISE“– (15).”

 

The texts, “ The method to reduce temperature………………..35% from the pressure side of the gas turbine blade feather.” In     “4. Conclusions” NEED  to be revised

The state of arts of the manuscript can be enhanced by citing and  using the following articles in the links: doi:10.1088/1757-899X/1107/1/012025;    DOI: 10.3390/en13226018;    DOI: 10.1016/j.tsep.2021.101145;    DOI: 10.1007/s10973-021-10869-1;    DOI: 10.1016/j.ijthermalsci.2020.106738 a

 

 

 

 

Comments for author File: Comments.docx

Author Response

All comments have been taken into account

Author Response File: Author Response.docx

Reviewer 2 Report

Comments for author File: Comments.pdf

Author Response

All comments have been taken into account

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

 

The Abstract needs a minor revision

The grammatical construction of the introductory aspect need a minor revision

 

 

Revise, “The research object in this paper is the radial channel of the cooling system that is specific for the mid-chord region of the blade feather midpoint..”

Improve the content “To augment heat ex-change in the channel finsribs are implemented, the use of which allows increasing the heat exchange surface area and ad-ditionallyadditionally swirl the flow by periodical boundary layer separation.”

 

 

 

 

Table 1.

More references  needed to enhance the state of arts of the manuscript. These can be cited :    DOI: 10.1088/1757-899X/1107/1/012025;    DOI: 10.3390/en13226018;     DOI: 10.1007/s10973-021-10869-1;     DOI: 10.1088/1757-899X/1107/1/012222; D OI: 10.1016/j.tsep.2021.101145

 

 

Conclusion needs a major revision

Comments for author File: Comments.docx

Author Response

We took into account your comments and made changes. Thank you!

Author Response File: Author Response.docx

Reviewer 2 Report

The original manuscript has too many mistakes and inappropriateness in writing and content, showing that the authors did not take it seriouly. The reviewer hope the authors could do better in future work.

Author Response

Thanks for the recommendation! In the future, we will treat articles more responsibly.