Study on the Location Determination of Building Fire Points Based on Acoustic CT Temperature Measurement

Round 1

Reviewer 1 Report

Reviewer:

This study used numerical simulation to study on the location determination of building fire point based on acoustic CT temperature measurement. However, certain major issues in this paper require further revision. The specific issues that need to be addressed are as follows:

1 The research conclusions of this article are all based on data obtained from fire dynamics simulator (FDS) and no relevant experiments have been conducted to obtain experimental data. Can additional experiments be conducted to better demonstrate the effectiveness of this method.

2 The images in the paper need to be modified to improve their clarity. The format of the paper, including tables and references, needs to be reviewed and corrected. Additionally, the paper requires more extensive references and theoretical support.

3 On line 127, This paper shows that the building space of 20× 20 ×5 m³ is constructed, and the geometric model is evenly divided into 16,000 grids. Is the grid size setting reliable? Please verify the independence of the grid

4 On line 151, This paper shows that after exploring various forms of fitting, it was determined that the 4-layer neural network provided the higher accuracy and lower fitting time, However, This article does not provide an introduction to the relevant fitting schemes or a comparison of the results. Please provide a comparison of accuracy and operation time to better understand the article for readers.

5 In Figure 5, The cross-section meshing scheme is 9x9、10x10 and 11x11. Please explain why these three options were chosen and whether they are representative.

6 In analysis of reconstruction results, compared with the basic temperature data, the reconstruction temperature maximum of these three schemes is lower, Please provide a reasonable explanation for why this phenomenon occurs in order to improve the reliability of the reconstruction results

 

unmistakable and logical

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

This study has some practical value. To meet the requirements for publication, the following revisions need to be made.

(1) Some of the figures are not particularly clear. The resolution of the figures needs to be improved or using vector graphics. The text within some of the figures is small and not convenient to review.

(2) The overall structure of the article is quite confusing. There is no clear division into sections for methods, results, and discussions.

(3) Reproducibility and accuracy of data are key points to consider. The authors need to clearly describe how the results were measured or calculated.

(4) Language and writing in the article should be improved.

(5) The full name of CT is not given in the manuscript.

Language and writing in the article should be improved.

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 3 Report

The phenomenon, that the speed of sound in gases has a pronounced temperature dependence, can be exploited for non-contact temperature determination methods. The study of Gao et al. deals with a trial to use acoustic temperature determination to identify the locations of fire sources in buildings. The authors evaluated the applicability of acoustic computed tomography (CT) measurement technique for this purpose. Therefore, the presented study has an interesting subject of investigation. However, the content of the article has been limited to numerical simulation. That means, the basic data were not obtained from real experiments. Instead, the acquisition of the basic temperature field data was performed with a fire dynamics simulator (FDS). Then, these basic data were reconstructed with two iterative algorithms: Simultaneous algebraic reconstruction technique (SART) and Least Squares QR-Decomposition (LSQR). The SART yielded somewhat better results than LSQR, but the iteration was somewhat more time-consuming. The fire source localization yielded fairly good results. That means no verification by experimental data is provided. I know, that close to reality experiments of fire scenarios are laborious and expensive, but they could verify unambiguously, whether the novel approach may have the potential for practical application. In addition, motion of the gaseous medium along the sound propagation path seems not to be considered, but it could influence the determination (hot gas has strong convection current).

Nevertheless, the manuscript should be published after performing some alterations and supplementations (see below).

Please insert information on the hardware used to carry out the iteration processes.

Please check the manuscript carefully, insert missing blanks and remove some errors in spelling and grammar errors.

Line 87/88: the following sentence does not make sense: “… with the ratio of the specific heat to the specific heat; …”

Line 75: exchange “travellingt” by “travelling”.

Please check figure 5: (b) and (c) are certainly not correct!

Please improve the conclusions part!

Line 384/385: It is not clear for me, what the following sentence means (please replace it by a better one): “Relatively speaking, the number of grids under the SART is higher than the LSQR algorithm.“

The phenomenon, that the speed of sound in gases has a pronounced temperature dependence, can be exploited for non-contact temperature determination methods. The study of Gao et al. deals with a trial to use acoustic temperature determination to identify the locations of fire sources in buildings. The authors evaluated the applicability of acoustic computed tomography (CT) measurement technique for this purpose. Therefore, the presented study has an interesting subject of investigation. However, the content of the article has been limited to numerical simulation. That means, the basic data were not obtained from real experiments. Instead, the acquisition of the basic temperature field data was performed with a fire dynamics simulator (FDS). Then, these basic data were reconstructed with two iterative algorithms: Simultaneous algebraic reconstruction technique (SART) and Least Squares QR-Decomposition (LSQR). The SART yielded somewhat better results than LSQR, but the iteration was somewhat more time-consuming. The fire source localization yielded fairly good results. That means no verification by experimental data is provided. I know, that close to reality experiments of fire scenarios are laborious and expensive, but they could verify unambiguously, whether the novel approach may have the potential for practical application. In addition, motion of the gaseous medium along the sound propagation path seems not to be considered, but it could influence the determination (hot gas has strong convection current).

Nevertheless, the manuscript should be published after performing some alterations and supplementations (see below).

Please insert information on the hardware used to carry out the iteration processes.

Please check the manuscript carefully, insert missing blanks and remove some errors in spelling and grammar errors.

Line 87/88: the following sentence does not make sense: “… with the ratio of the specific heat to the specific heat; …”

Line 75: exchange “travellingt” by “travelling”.

Please check figure 5: (b) and (c) are certainly not correct!

Please improve the conclusions part!

Line 384/385: It is not clear for me, what the following sentence means (please replace it by a better one): “Relatively speaking, the number of grids under the SART is higher than the LSQR algorithm.“

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

This revised manuscript meets the criteria for publication.