Round 1

Reviewer 1 Report

Dear authors,

I red your paper „Study on Radial Loss Model and Law of Fractured Formation Drilling Fluid“ and below you can see my suggestions and comments so that your paper will be even better:

1.      According to Instructions for authors chapter numbering starts from 1 (1. Introduction should be...)

2.      What is H-B model? When it is mentioned for the first time, the full name should be given, and then the abbreviation can be used. The same comment applies to other abbreviations.

3.      Figure 5. Fluids with different rheological modes, translate into english

4.      Watch out for typos, so I recommend reading the whole paper again and fix it

5.      In Figures on legend put units (where it should be), not only values, as well as put a space between the text and the unit on the axis

6.      The discussion should be expanded with the data obtained on the basis of your results, and then the conclusion should be supplemented with concrete data

7.      Chapter 6. Patents should be removed because there is no any text

Also, in order to get a little broader insight into the topic related to mud lost in naturally fractured reservoirs I recommend reading the following paper: https://doi.org/10.3390/app11020767

Best regards!

Reviewer

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Study on Radial Loss Model and Law of Fractured Formation Drilling Fluid, By Zelong Xie, Zhu Liang, Shubo Bi, Ji Hui,Tianyi Wang, Mengting Huang, Zhang Hao and Huimei Wu

This study is concerned with the drilling, and analyzing the real-time leakage. Based on the principles of fluid mechanics and using Herschel-Bulkley drilling fluid, tortuosity and deformation index of fractures parameters are introduced so that the radial leakage model is intended to be improved numerically. It is shown that the larger the curvature of the fracture, the rougher the fracture, and the smaller the leakage rate and cumulative leakage rate. Moreover, as the extending length of the fracture increases, the invasion of drilling fluid decreases, and the leakage rate slows down. The results are beneficial in structurally developed fractured formations.

In view of important contributions to the specific topic, the paper can be published in the MDPI: Processess, after adressing the following main issues:

A) Language seems fine overall. There are some typos needing attention.

B) Abstract is too long and should be trimmed.

C) Introduction is Okey overall. Although non-Newtonian fluids are mentioned, less survey is provided. Few more literature can be added, including “Flow of non-newtonian fluids in a pipe (https://doi.org/10.1016/0377-0257(90)80015-R)” and “Eyring-Powell fluid flow through a circular pipe and heat transfer: full solutions (DOI: 10.1108/HFF-12-2019-0925)”.

D) In part b of figure 1 there seems no fracture at all.

E) In figure 3, should the reader understand a muddy flow in a tube?

F) I am happy to see equations (1-6) which help a non-expert to seize the model. Is Eq.(7) solved from Eq.(6)?

G) It is not clear how to get Eq.(9).

H) Viscosity models in figure 5 contain some Chinese language.

K) Eq.(12) is not continuity equation, but rather looks like a momentum equation. is the fracture width behaves like density?

L) “omitting the high-order term after Taylor expansion” refers to what order?

M)- Using the approximate method, for what perturbation variable, in Eq.(17)?

N) - I think, the most important equation here in Eq.(18). Can you find analytical solution(s) for this equation?

P) - I am not convinced why the simulation is based on the parameters given on Table 1. Are these universal?

R) - A series of similar pictures are shown. From these, viscosity coefficient of the drilling fluid gradually decreases with increasing time. Does it reach a steady state after a long run?

Author Response

请参阅附件。

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

I believe that the manuscript has been sufficiently improved so I suggest publication. 

Reviewer 2 Report

A serious and satisfactory revison has been made by the authors in parallel to the comments.