Experimental Study of Condensation Heat Transfer and Pressure Drop inside a Small Diameter Microfin and Smooth Tube at Low Mass Flux Condition

Round 1

Reviewer 1 Report

This research is about the condensation heat transfer and the pressure drop in the micro fin and smooth tubes. The authors investigated the effects of tube diameter, quality and mass flux on the heat transfer coefficient and the pressure drop. Moreover, the experimental data are compared with open literature. This evaluation of the existing correlation is valuable and more useful for the design of air-conditioner and refrigerator. Minor comments are as follows:

 

1. Figs.11-14: Are the heat transfer coefficients average values in the tubes? If so, please add the explanation of the data reduction, since the local heat transfer coefficient can be obtained in Eqs.(1) and (2) by the thermocouples.

 

2. P.16. Line 379 Ref.21: The year of publication is not correct. It is 1964.

Author Response

We wish to express our appreciation to the reviewers for their insightful comments on our paper. The comments have helped us significantly improve the paper. We have modified the manuscript according to the reviewers’ comments, and detail corrections are listed point by point.

Comment 1:

Figs.11-14: Are the heat transfer coefficients average values in the tubes? If so, please add the explanation of the data reduction, since the local heat transfer coefficient can be obtained in Eqs. (1) and (2) by the thermocouples.

Answer to the comment No. 1:

The heat transfer coefficients are not average values in the tubes. The condensation heat transfer coefficients are the local values in the tubes which are shown in Figs. 11-13 and can be obtained by Eq. (1) and (2). Therefore, we think that no need to add an additional explanation in the data reduction part.

Additionally, In Fig. 14 shows the effect of tube diameter on average condensation heat transfer coefficient and this data is collected from the open literature. We have added the word “Average condensation” in Fig. 14 title, P. 11, Line 265. Thank you.

Comment 2:

 P.16. Line 379 Ref.21: The year of publication is not correct. It is 1964.

Answer to the comment No. 2:

Yes, the reviewer is right. We have corrected the year of publication in P.16, Line 381, Ref.21.Thank you.

Author Response File: Author Response.pdf

Reviewer 2 Report

•    Please add a dot (.) at the end of keywords.

•    The English language should be revised be a native.

Paper does not have any “Author contribution” part.

Please provide a picture from experimental apparatus.

•    Please draw figures in color.

•    Some references like [1 & 2], [11-14], [16-22], and [24-27] are very old and therefore, they are abolished. May the reviewer ask the authors to change these references to newer ones? Some suggested references are as below:

1)      https://www.sciencedirect.com/science/article/pii/S0017931018309165

2)      https://www.sciencedirect.com/science/article/pii/S0017931017314783

3)      https://link.springer.com/article/10.1007/s10973-017-6746-x

•    Review more recent works can expand the introduction.

 

Author Response

We wish to express our appreciation to the reviewers for their insightful comments on our paper. The comments have helped us significantly improve the paper. We have modified the manuscript according to the reviewers’ comments, and detail corrections are listed point by point.

Author Response File: Author Response.pdf