Lattice Boltzmann Simulation on Droplet Flow through 3D Metal Foam

Round 1

Reviewer 1 Report

This paper demonstrates the hydrodynamic flow characteristics of droplets passing through metal foam and explains the process by Lattice Boltzman Method. The paper is written well and can be accepted for publication after minor corrections listed below.

Abstract: Must be sharp and precise and only list values/facts which are widely known to audience. So it can be shortened.

Introduction: Introduction is written well.

Experimental Part and Results can be separate heading. There are too many figures for a paper. They must be combined or many moved to supplementary if required such as  Fig. 2,3,6 and 11 are too small to be separate figures. They must be readjusted.

All in all, the paper is suitable for publication in processes.

Author Response

Point 1: Abstract: Must be sharp and precise and only list values/facts which are widely known to audience. So it can be shortened.


Response 1: The abstract is shortened into 135 words.

The simulated results showed that the capillary number, droplet size, pores diameter and thickness of metal foam have significant effect of the droplet deform and breakup when droplet pass through the metal foam. To avoid the calescence of two droplets at the inlet zone of the metal foam, the distance between droplets should be larger than 3 times diameter of the droplet.(line 22-25)

Point 2: Experimental Part and Results can be separate heading. There are too many figures for a paper. They must be combined or many moved to supplementary if required such as Fig. 2,3,6 and 11 are too small to be separate figures. They must be readjusted.

Response 2: In the revised manuscript, Fig.2 and Fig.3 is combined. Fig.4 , Fig. 6,  Fig. 11 and Fig.16 was moved to supplementary.

Author Response File: Author Response.docx

Reviewer 2 Report

Comments

The authors should present the velocity field of the physical model as presented in Fig. 5 Discussion on model validation should be included

Author Response

Point 1: The authors should present the velocity field of the physical model as presented in Fig. 5 Discussion on model validation should be included

Response 1: In the revised manuscript, the velocity field of the physical model is present in Fig. 3. The experimental results using Plexiglass tube are used for the validation of the LBM simulated ones as showing in chapter 4.2.

Author Response File: Author Response.docx

Reviewer 3 Report

Overall this is a well-written paper. I noted a few minor blemishes, which I have listed below, and would recommend a final reading by a fluent English speaker. 

Comments (numbers are line numbers):

107 “the matrix of metal foam has no any sorption” I assume “any” should be deleted. More important scientifically: Even weak adsorbents may adsorb significant amounts in very small pore spaces.  How was this statement validated experimentally? 167 et seq. “x is a discrete lattice location”. Is this a 1D location or a 3D vector? From subsequent equations it appears to be 3D, in that case, bold notation and a more suitable symbol should be chosen. Either way, this should be clarified. 172. Does “*” symbolise a dot product multiplication? Again standard mathematical notation should be used. 188. I did not find a definition of “tau” in eq. (8) and subsequent equations. 189 et seq. “component” has a specific meaning in the chemical literature and a different, but specific meaning in the mathematical literature. In the context here “component” appears to have the meaning of “molecule” or “particle”. This needs to be clarified. 205. “in the solid lattice” I assume this means “in the pore space of the solid lattice”, not in the inter-atomic interstices.

 

Author Response

Point 1: 107 “the matrix of metal foam has no any sorption” I assume “any” should be deleted. More important scientifically: Even weak adsorbents may adsorb significant amounts in very small pore spaces. How was this statement validated experimentally?

Response 1: As you said, this expression is inaccurate. We have rewrite this sentence in the revised manuscript. Actually, the adsorption force between the wall and the medium is considered in the simulation by including parameters of interaction strength between different components.

100 Porosity of metal foams is usually larger than rock or soil, therefor, metal foams have a stronger circulation capacity and less capillary.

Point 2: 167 et seq. “x is a discrete lattice location”. Is this a 1D location or a 3D vector? From subsequent equations it appears to be 3D, in that case, bold notation and a more suitable symbol should be chosen. Either way, this should be clarified. 172. Does “*” symbolise a dot product multiplication? Again standard mathematical notation should be used.

Response 2:  In the revised manuscript, all the discrete lattice location are presented as vector style , and symbol of multiplication of vectors is changed into “·”.

Point 3: 188. I did not find a definition of “tau” in eq. (8) and subsequent equations.

Response 3: The “tau” in eq. (8) is defined as relaxation parameter which can be found on line 163.

Point 4: 189 et seq. “component” has a specific meaning in the chemical literature and a different, but specific meaning in the mathematical literature. In the context here “component” appears to have the meaning of “molecule” or “particle”. This needs to be clarified.

Response 4: To eliminate misunderstandings, “component” is changed into “particle” in the revised manuscript

Point 5：205. “in the solid lattice” I assume this means “in the pore space of the solid lattice”, not in the inter-atomic interstices.

Response 5: Your statement is more accurate, the sentence is changed into “when is in the pore space of the solid lattice”

Author Response File: Author Response.docx