A physics journal has informed an embattled rocket scientist that it will retract three of his papers, citing concerns raised by the retraction of another of his papers last year.
All three articles appear in Physics of Fluids, published by AIP Publishing, and describe a phenomenon called “Sanal flow choking.” As we reported last year, some scientists have denounced the concept as “absolute nonsense.” The researcher who coined the phrase is the lead author on all papers, V.R. Sanal Kumar, a professor of aerospace engineering at Amity University in New Delhi.
The papers are:
- “The theoretical prediction of the boundary-layer-blockage and external flow choking at moving aircraft in ground effects,” published in March 2021 and cited 24 times, according to Clarivate’s Web of Science.
- “Universal benchmark data of the three-dimensional boundary layer blockage and average friction coefficient for in silico code verification,” published in April 2022 and cited 12 times.
- “In vitro prediction of the lower/upper-critical biofluid flow choking index and in vivo demonstration of flow choking in the stenosis artery of the animal with air embolism,” published in October 2022 and cited 11 times.
AIP Advances, which is owned by the same publisher, retracted a paper by Kumar last year.
In emails seen by Retraction Watch, the editorial office of Physics of Fluids referenced the October retraction, telling Kumar “concerns were raised related to the content of the manuscripts due to previous work retracted by AIP Advances.”
Although the papers aren’t yet marked as retracted, the journal’s editorial office told Kumar in a May 16 email they planned to retract his work due to “significant issues affecting the reliability of the findings and conclusions of these three articles.” The decision followed a post-publication review, which found a theoretical framework that “fundamentally violates the second law of thermodynamics.” In addition, three of the citations in one paper were to retracted studies.
In the initial peer reviews for each article, which Kumar provided to us, at least one reviewer stated they did not recommend publication of the manuscript without substantial revision. Kumar also provided his responses to the editor and reviewer comments purportedly addressing the issues.
In an email dated Jan. 6, 2021, one referee’s comments about one of the manuscripts stated “it is difficult to draw the conclusion from them as to why this study has been carried out,” and “I cannot support publication unless the authors undertake all the above actions in full.” Kumar provided us his responses to the reviewer comments, as well as a Feb. 3, 2021 email from the journal that the revision had been accepted and another email dated February 6 that the journal had chosen it as a highlighted “Editor’s Pick.”
In addition to retracting the three published papers, the journal told Kumar it was placing five of his submitted/accepted manuscripts on production hold “pending the results of our investigation.”
Kumar responded to the journal’s email to “formally and unequivocally reject” the decision given the “life saving relevance” of the papers. He called the claim about the paper violating a rule of thermodynamics a “misinterpretation” and said the retractions for cited studies are “under formal investigation.” Notably, Kumar was lead author on all three.
Kumar told us in an email the retractions are a “coordinated, international campaign to sabotage a breakthrough scientific theory with immediate applications across aerospace, biomedical, and national defense sectors.” He also told us he has formally complained to the Committee on Publication Ethics and “notified the relevant government authorities.”
When we asked if they still planned to retract the articles, the journal said they couldn’t “yet comment publicly on the outcome of the investigation.”
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Interestingly, on May 6, 2025, AIP announced the appointment of an “interim” editor-in-chief for Phys. Fluids:
https://publishing.aip.org/about/news/announcing-a-leadership-transition-for-physics-of-fluids/
Some context from a fluids researcher: Physics of Fluids was for many years the second most prestigious Journal in our discipline, behind the Journal of Fluid Mechanics. A few years ago the entire editorial board resigned, and started Physical Review Fluids, which is now the second most prestigious and rigorous journal. Physics of fluids, with an entirely new editorial board, will apparently publish absolutely anything, with only the most cursory review. The very fast review times have actually increased the impact factor, but the quality is through the floor.
I think this is the first time a fluids journal has made it into retraction watch, and it’s not surprising at all that it is physics of fluids.
I could say that they had lost their liquidity
PRF > PoF
Thank you for sharing that.
Quick sleuthing of some of their papers gives a lot of insight into what might be going on here. One of their more prominent articles (now retracted) “Lopsided Blood-Thinning Drug Increases the Risk of Internal Flow Choking Leading to Shock Wave Generation Causing Asymptomatic Cardiovascular Disease” cites 83 other articles for the statement “a decrease in diastolic blood pressure (DBP) increases cardiovascular risk.” While I have not gone through every one, many do not or barely contain “blood pressure” in the entire article.
Would you be suspicious of a colleague who always highly cites themselves, has 43 co-authors on a theoretical prediction based article, cites articles that barely even contain the phrase blood pressure let alone the claim being made, and starts an abstract with “The discovery of Sanal flow choking in the cardiovascular‐system calls for multidisciplinary and global action…”? Maybe I am wrong and a global cabal is after some random Indian academic, which is definitely the most plausible explanation for their retractions.
And narcissistictically naming a putatively “breakthrough scientific theory” after oneself isn’t a red flag…
One paper in Scientific Reports was retracted for, among other reasons, being based on the assumption that blood is an ideal gas. Truth to tell, it’s not even an ideal – i.e. Newtonian – fluid, owing to the presence of numerous RBCs and platelets. As a result, blood actually becomes less viscous under pressure, making it under some conditions “thinner than water.” Sanal’s theories regarding blood flow are clearly worthless.