Hypersonic Research works Published in High Impact Factor Journal is Erroneous

This post should concern the Hypersonic researchers. It is about reporting a ridiculous research work published in a reputed journal which also declined to publish my “Comments” that reports the errors/mistakes of the published article. Firstly, I informed about the errors/mistakes of the published article to a retired Professor who is ex-Head of that Laboratory, then informed the first author of the article and finally reported to The Editor of the journal. Since all went in vain and my intention is to let other researchers know about the errors in the published article so that they can use the data with utmost caution and spare their time, I decided to publish it in an archive (http://viXra.org/abs/1903.0557) and provide its background here.

Paper title: Comments on “Aerothermodynamic Effects of Controlled Heat Release Within the Hypersonic Shock Layer Around a Large Angle Blunt Cone” [phys. Fluids 30, 106103 (2018)]

Link: http://viXra.org/abs/1903.0557

Paper title: Comments on “Aerodynamic Drag Reduction by Heat Addition Into the Shock Layer for a Large Angle Blunt Cone in Hypersonic Flow” [physics of Fluids 20, 081703 (2008)]

Link: http://viXra.org/abs/1903.0555

Please forward this to the concerned researchers which would save their precious time and effort. PS: I spend more than two years of my PhD convincing my Professor that the data given to me by my senior is wrong. This is one of the primary reason why I am very much concerned about this.

An article titled “Aerothermodynamic effects of controlled heat release within the hypersonic shock layer around a large angle blunt cone” was published in a Physics of Fluids journal in October 2018 (https://doi.org/10.1063/1.5046191). The Physics of Fluids journal is one of the highly reputed journal in the world of Fluid dynamics with an impact factor of ~2.3. This article was a featured article of that month.

This article is about investigating a flow physics of a spacecraft if its surface is coated with chromium using four different measurement techniques (heat flux using thin film sensors, temperature using pyrometry technique, shock stand-off distance using flow visualization technique) and also matched the experimental results with computational simulation (CFD) results. I found all the four measurement techniques were improperly used and the data was manipulated to achieve the desired results. On top of these, the test conditions itself were wrongly calculated which is used as an input to perform computational simulation. I discussed it with few experts. We found the scientific errors are substantial and so stupid. The errors are very obvious to any Experimental Hypersonic/Supersonic expert. One of the expert described it as “The article contains substantial claims with mere evidences from a vague research methodology with questionable outcomes”.

I contacted the first author of the paper and his answers were not convincing. So I decided to list out the major errors and send it to the Physics of Fluids journal to be published as “Comments”. The Editor immediately rejected it saying the first paragraph was mean-spirited. I immediately send an apologising letter and requested for resubmission. I rephrased the words and resubmitted my “Comments”. It was rejected again after the peer-review process. The first reviewer have strongly recommended my “Comments” for publication. Please find the detailed reviewers comments towards the end of the post. The second reviewer seems to have mistaken the manuscript type as “Full length paper” instead of “Comments” and refused it to publish it as a standalone paper as there is no new science involved. The second reviewer’s comments goes as follows:

“This article seeks to question the data presented in an earlier paper and, in itself, adds nothing new to the science involved. It seems to me that the objections should be taken up directly with the authors of the original paper, rather than being published as a standalone paper. If the author wishes to publish on this matter then I would recommend that they complete a set of experiments of their own, at similar conditions, and highlight any differences.”

As a policy of Physics of Fluids, "Comments are to address scientific issues in a very concise and substantive manner with no harsh criticism" (https://aip.scitation.org/phf/info/policies). It is basically to notify the errors in the article to other researchers so that the other researchers can use the data with utmost caution. In this case no new science material or additional experimental data are required as suggested by the second reviewer. Many such comments have been published in the past. So I immediately wrote an email to the Associate Editor clarifying that my manuscript type is "Comment/Response" and not "Full length paper" for which I received a reply from The Editor that they are not at liberty to publish material that has not satisfied the reviewers.

I didn’t expect such vague statements as a reason for rejection from a highly reputed journal. I believe that people in academic research can get a feel of this situation. Whatever!!! Open access journal and social networking sites gives life to such issues.  

In fact the same research group have published an article in 2008 in Physics of Fluids titled “Aerodynamic drag reduction by heat addition into the shock layer for a large angle blunt cone in hypersonic flow“ (https://doi.org/10.1063/1.2944982). Another research group performed numerical simulations on this work and found a large discrepancy (>50%) with the experimental results. The results are published in (https://doi.org/10.1177/0954410013490849) International Journal of Heat and Mass transfer in 2014. I found the reason for such a discrepancy is due to improper data analysis of the experimental signals and I notice similar kind of lethargic research work with the present one as well. The same is also reported in an open access journal (http://viXra.org/abs/1903.0555).

Please find the details of my “Comments” for both the papers in the following links:

Paper title: Comments on “Aerothermodynamic Effects of Controlled Heat Release Within the Hypersonic Shock Layer Around a Large Angle Blunt Cone” [phys. Fluids 30, 106103 (2018)]

Link: http://viXra.org/abs/1903.0557

Paper title: Comments on “Aerodynamic Drag Reduction by Heat Addition Into the Shock Layer for a Large Angle Blunt Cone in Hypersonic Flow” [physics of Fluids 20, 081703 (2008)]

Link: http://viXra.org/abs/1903.0555

Please cascade the information to the concerned researchers which would save their precious time and effort.

Referee Comments:

Referee #1 (Comments to Both Author and Editor):

I have read the comments and the associated article by Deep and Jagadeesh. I agree with the present author that the purported effects on the flow field due to the chromium coating are based on very tenuous experimental data and a weak theoretical analysis (Ref. 14 from the original article). I encourage the publication of the comment by Anbuselvan because it raises fair questions about the validity of the prior work. I cannot comment on all of the specific issues that Anbuselvan raises, but they appear to be valid concerns and should be brought to light.

Regarding the previous paper, I have the following issues:

1. the test time is extremely short and during the so-called steady test time, there are very large variations in pitot pressure and heat flux. These variations are of the same scale as the differences supposedly measured.

2. The authors say that they ran at least 5 cases, but there is nothing presented to show the resulting variation. Why not?

3. The estimates of the free-stream conditions have unrealistically small error bars, as do all other reported experimental data. How can the heat flux be measured to 2.3% accuracy, when there are order 30% variations in heat flux during the test time. This is ludicrous at best.

4. Why not just do some runs with N2 as the test gas on the chromium coated model; that would at least provide some verification that an inert gas would not produce the same effect -- though given the variations discussed above, I am not sure these effects can be discriminated.

5. Reference [14] is qualitatively valid at best. It provides no support to the experimental data shown in the subject paper.

Referee #2 (Comments to Both Author and Editor):

This article seeks to question the data presented in an earlier paper and, in itself, adds nothing new to the science involved. It seems to me that the objections should be taken up directly with the authors of the original paper, rather than being published as a standalone paper. If the author wishes to publish on this matter then I would recommend that they complete a set of experiments of their own, at similar conditions, and highlight any differences.