Congratulations to the ASME Fluids Engineering Division on their 100th anniversary

Earlier this month, I learned that the Fluids Engineering Division (FED) of the American Society of Mechanical Engineers (ASME) is celebrating its 100th anniversary this summer at their annual summer meeting (FEDSM2026).  They may be the oldest fluid mechanics-specific professional society in the United States...let's take a look at the evidence for this claim.

First, ASME was founded in 1880, and its Hydraulics Division (HYD) was formed in 1926, with Prof. Lewis F. Moody as a prime mover in its creation.  Its first separate division conference was held in 1961.  Prof. Robert C. Dean led the effort to change its name to the Fluids Engineering Division (FED) which succeeded in 1963.  A restructuring occurred in 1989-1990, but the name remained.  There was also a Committee on General Hydraulics which existed between 1938-1940, led by Murrough P. O'Brien, and later a Fluid Mechanics Committee, formed in 1957 by Dean, now called the Fluid Mechanics Technical Committee (FMTC).  The Journal of Fluids Engineering was founded in 1973, also under Dean, its first editor.  I've pulled this information from the article by Cooper et al. (2016).

We must turn now to the American Society of Civil Engineers (ASCE), founded much earlier (1852).  Its Hydraulics Division was formed in 1938, the 12th such division formed.  Fred C. Scobey of USDA was the prime mover of that effort.  Its first specialty conference was held in 1950, and its Journal of the Hydraulics Division began in 1956.  In 1982, the journal was renamed the Journal of Hydraulic Engineering.  A 50th anniversary book for the division was published in 1990, but I have not been able to see a copy.  My information is drawn mainly from Petersen (2002).  It is unclear to me from the society's website whether the Hydraulics Division, or its specialty conference, still exist, but the journal definitely does.

The American Physical Society (APS, founded in 1899) created its Division of Fluid Dynamics (DFD) in 1947, its fourth division.  Raymond J. Seeger was the prime mover of this effort.  The first annual meeting was held in 1949, though sessions were sponsored at the 1948 APS annual meeting, including a joint meeting with the Institute of Aeronautical Sciences (a predecessor to the AIAA, about which more later).  However the APS did not start a special fluid mechanics journal until 2015, Physical Review Fluids.  Prior to that, the DFD collaborated with the American Institute of Physics (AIP) in the publication of Physics of Fluids, founded in 1959 under Francois Frenkiel.  Some historical information on the DFD can be found in this piece by Russell Donnelly.

For the remainder of this post, information is drawn from Wikipedia and/or the websites of the professional societies themselves.

The American Institute of Aeronautics and Astronautics (AIAA) was formed in 1963 from the merger of the Institute of the Aerospace Sciences (founded in 1932 under the name Institute of Aeronautical Sciences, mentioned above), and the American Rocket Society, founded in 1930.  At one time the AIAA sponsored a Fluid Dynamics Conference, but it does not seem to exist anymore.  They do have a Fluid Dynamics Technical Committee, within their Aerospace Sciences Group.  I do not know when it was formed, but it can't be older than AIAA itself.  AIAA does not seem to have a specialty journal for fluids; rather fluids papers appear across the constellation of their journals on other subjects.

The same about the journals can be said about the American Institute for Chemical Engineering (AIChE), founded in 1908.  They don't seem to have a specialty journal, conference, or division or forum dedicated to fluids, as the topic basically pervades much of the discipline, as it does for AIAA.

Indeed, many professional societies in science, mathematics, engineering, and the Earth, environmental, and planetary sciences make use of fluid mechanics, and many of their practitioners carry out fundamental research in fluids.  Fundamental and applied topics in fluids research pervade across multiple technical areas within these professions, so often they do not have a fluids-specific unit, journal, or conference.  Examples include the Society for Industrial and Applied Mathematics (SIAM), the American Geophysical Union (AGU), and the American Meteorological Society (AMS).  However, the AMS does host an annual Atmospheric and Oceanic Fluid Dynamics (AOFD) conference.  It has not always been annual (the most recent, just held earlier this week, was called the 25th, but I coauthored a presentation given at the 13th in 2001), so I'm not sure when it began.  I have seen an announcement for the 2d AMS Atmospheric and Oceanic Waves and Stability conference in 1978, so perhaps this is the same conference under a different historical name?

So to conclude, the major U.S. professional society units that specialize in fluid mechanics appear to be the ASME's FED and the APS's DFD, both of which sponsor annual conferences and journals (JFE and PR Fluids).  The AIAA has a technical committee but no special conference or journal.  The AMS also has their AOFD annual conference, and the ASCE maintains the Journal of Hydraulic Engineering. To these we can add the AIP's Physics of Fluids journal.

The surviving units, ASME FED and APS DFD, were created in 1926 and 1947 respectively, so indeed FED is the oldest that I know of in the United States.  The ASCE has the oldest journal discussed here, however, since JHE dates to 1956, with PoF following in 1959, JFE in 1973, and PR Fluids in 2015.  Finally the oldest surviving conference discussed here is DFD's, starting in 1949, followed by FEDSM in 1961, and AOFD possibly dating to sometime in the 1970s.

References

P. Cooper, C. S. Martin, and T. J. O'Hearn, 2016:  History of the Fluids Engineering Division.  Journal of Fluids Engineering, 138:  100801.

M. S. Petersen, 2002:  Summary of the Hydraulics Division- ASCE (1938-1988).  Environmental and Water Resources History, ed. by J. R. Rogers and A. J. Fredrich, Sessions at ASCE Civil Engineering Conference and Exposition, Nov. 3-7, 2002, Washington, DC., pp. 193-194.

A Review of Abrahm Lustgarten's "Run to Failure"

On April 20, 2010, the Deepwater Horizon oil drilling platform was completing the task of drilling a pipe into BP's Macondo well in the Gulf of Mexico.  The pipe experienced a blowout, and the blowout preventer failed, resulting in an explosion and eventual sinking of the platform.  Eleven workers were killed, and seventeen were seriously injured.  The rupture of the pipe resulted in a massive oil spill event that lasted 86 days.

The disaster was eminently preventable.  Investigation of its causes has focused on a number of technical and engineering issues; however the larger context was BP's corporate culture.  Understanding that culture requires a deeper study of BP's checkered history of operations management and industrial safety.  The book Run to Failure, by Abrahm Lustgarten (2012), provides just that.  Written in conjunction with the Frontline documentary, The Spill, it provides an in-depth examination of BP's history in North America, beginning in 1989 when John Browne was named head of worldwide exploration and production.  Browne would later become BP's chief executive, and on his watch there were major disasters at two of BP's legacy assets:  its Texas City refinery and its operations on Alaska's north slope, site of its Prudhoe Bay oil fields, as well as an extensive pipeline network.  These legacy assets were considered sources of revenue to be milked as much as possible, but they were not opportunities for growth, and thus infrastructure investments were minimized.

After the prologue, which describes the Deepwater Horizon accident and introduces the book, the next fourteen chapters are dedicated to events prior to that accident.  We observe a corporate culture where site managers were frequently rotated, while being pressured to produce financial results.  This produced a short term mentality, perpetual cost cutting, and an avoidance of investing in infrastructure maintenance, even where safety and the environment were at risk.  Safety management focued on the less expensive "slips and trips" rather than the vastly more expensive process safety.  Workers who raised concerns were ignored, and whistleblowers were blacklisted.  An attitude of "run to failure" pervaded at BP's legacy assets.  However, even BP's preferred areas for investment, such as the Gulf of Mexico, provided an example of corner-cutting in the rush to start making money.  The near sinking of BP's Thunder Horse platform during Hurricane Dennis in 2005 was caused by the mistakenly backward installation of several check valves in the platform's pontoons.

BP's poor safety record is compared unfavorably with those of other major oil companies, particularly Exxon, which seems to have taken to heart the lessons of the notorious Exxon Valdez oil spill.  The rate of spills and other process accidents for BP was usually several times higher than that of its competitors.

The last two chapters, and the epilogue, return to the Macondo well and the Deepwater Horizon accident.  The exposition of events reveals a series of poor decisions as well as equipment failures that all point to a culture of corner cutting in the rush to get results.  It provides a case study of engineering and business decision analysis and ethics.  The book ends with evidence that BP hasn't really changed its corporate culture, and implies that the company's next disaster will occur on Alaska's north slope.  A post from earlier this year in the Columbia Journalism Review, by Alexis Sobel Fitts, shows that BP is even now aggressively trying to influence public perception of the Deepwater Horizon disaster.

One issue that arises is the role of federal and state government regulators.  The author discusses this issue, including a number of agencies, though the primary emphasis is on the Environmental Protection Agency.  This is perhaps due to his access to very candid sources from that agency.  There is relatively little discussion of the US Department of Interior's Minerals Management Service (MMS); fortunately you can read more about the role of this obscure agency in a May, 2010, Rolling Stone article by Tim Dickinson.  I wish that Lustgarten had incorporated more discussion of other regulators, including Dickinson's findings.

Run to Failure has been reviewed in a number of scientific journals such as Nature (Mascarelli, 2012).  The most useful reviews in my view are those by Peter Dykstra at Enivonmental Health News (here), and Matthew T. Huber (2013) in Contemporary Sociology.  I strongly recommend this book for those interested in engineering and business ethics, corporate culture, and the energy industry.

References

Matthew T. Huber, 2013:  Review of Lustgarten (2012).  Contemporary Sociology, 42:  400-401.

Abrahm Lustgarten, 2012:   Run to Failure:  BP and the Making of the Deepwater Horizon Disaster (W. W. Norton, New York).

Amanda Mascarelli, 2012:  Plumbing the depths.  Nature, 483:  154-155.

Evolution of airplanes: a follow-up

I thank Prof. Bejan for graciously replying to my critique of his work in a previous post.  Permit me to follow up briefly here.

Bejan is correct that his earlier publications have cited Tennekes and the others.  He is also right that the earlier writers did not include land and aquatic locomotion in their analyses.  I was aware of Bejan's 2006 paper with Marden (which cites Tennekes only as a data source, not for analysis) but have not seen his 2000 book published by Cambridge U.P.  I thank Prof. Bejan for clarifying these points, although my original post did make many of them already.

Nonetheless, Bejan's 2014 paper makes a specific point about the Concorde case, which Tennekes has discussed at length, as I showed.  A citation in Bejan's 2014 paper in the context of the Concorde discussion would have been pertinent for readers.  As it stands, the 2014 paper makes it seem that the 'outlying' nature of the Concorde on the diagram is a new finding, when it is not.

Bejan's comment also offers a very important distinction, one that I strongly affirm.  A purely empirical analysis of observational data is a wholly different activity to first-principles modeling of such data, especially when the latter is then validated by empirical data.  Many scientists indeed fail to appreciate this distinction.  However, the quantitative predictive modeling in Bejan's 2014 paper seems to be based on basic aerodynamic scaling arguments.  The link with evolution seems at best a metaphor; it is not clear to me that the evolutionary component of Bejan's work is predictive in any quantitative sense.  I stand by my previous comments on interpreting data, particularly the pteranadon case.  Being an outlier on the graph does not prevent the pteranadon for being fit for its ecological niche in its day.  This would seem to limit the scope of the evolutionary metaphor when linked to specific aerodynamic scaling arguments.   My methodological criticisms of correlation analysis also remain valid.

The "evolution" of airplanes: DTLR is not impressed

About three weeks ago, the Journal of Applied Physics published a paper by Adrian Bejan and collaborators, “The evolution of airplanes” (Bejan et al., 2014).  Bejan is a named professor of mechanical engineering and materials science at Duke University, and author of well-known textbooks on heat transfer and thermodynamics.  His co-authors are a Boeing engineer and Duke alum, Jordan Charles, and a French civil engineering professor, Sylvie Lorente, who is also an adjunct Duke professor.  The publisher and Bejan’s university both issued news releases about the paper, and Bejan wrote about his work at The Conversation.  Indeed, the paper has received a lot of online press coverage.  The publisher’s own Inside Science news organ did include some critical comments in its coverage; additional critical comments were also posted at The Conversation in response to Bejan’s post.  The criticisms focus on the overall logic and philosophy of the paper.  I strongly sympathize with these criticisms.  Here, however, I will provide an additional perspective beyond those aired by others thus far.

The paper presents a number of simple analyses including basic aerodynamic scaling arguments, compared favorably with empirical data about aircraft geometry and performance.  A particularly vivid graph in the paper shows empirical data comparing the body mass and velocity of airplanes with those of running, flying, and swimming animals.  The diagram (the paper’s Fig. 2) is reproduced below.

The Ref. 1 in the caption is Bejan and Marden (2006).  The authors make the point that the Concorde is an outlier in this diagram, and further comment as follows.

Looking at the graphs of this paper, we see that there is an outlier, the Concorde, which was perhaps the most radical departure from the traditional swept wing commercial airplane.  The Concorde’s primary goal was to fly fast.  In chasing an “off the charts” speed rating the Concorde deviated from the evolutionary path traced by successful airplanes that preceded it.  It was small, had limited passenger capacity, long fuselage, short wingspan, massive engines, and poor fuel economy relative to the airplanes that preceded it.  Even when it was in service, the Concorde did not sell, and only 20 units were ever produced (whereas successful Boeing and Airbus models were produced by the thousands).  Eventually, due to lack of demand and safety concerns, the Concorde was retired in 2003.  (Bejan, et al., 2014, p. 6.)

Except for the remark about the "evolutionary path", all of this is factual.  However, many of these observations are not original.  In a book published originally in Dutch in 1992, Henk Tennekes (2009) presents the following graph (his Fig. 2) comparing cruise speed and body weight; in the graph he tacitly ties cruise speed to wing loading (weight divided by wing surface area).  Although it does not include running and swimming animals, the graph is otherwise similar in spirit to Bejan et al.’s graph.

Tennekes attributes this sort of analysis to the former DuPont company head, Crawford H. Greenewalt, and later scholars, including Colin J. Pennycuick.  Greenewalt’s original analysis was published in 1962; see Tennekes (2009) for citations and sources of data.  Tennekes also derives a simple scaling formula relating wing loading to cruise speed.  The equation 2 referred to in the caption is a version of this scaling formula.

What does Tennekes have to say about the Concorde?  In Chapter 1, he writes the following.

Wasn’t it supposed to fly at about 1,300 miles per hour?  How come it didn’t have higher wing loading and therefore smaller wings?  The answer is that the Concorde suffered from conflicting design specifications.  Small wings suffice at high speeds, but large wings are needed for taking off and landing at speeds comparable to those of other airliners.  If it could not match the landing speed of other airliners, the Concorde would have needed special, longer runways.  The plane’s predicament was that it has to drag oversize wings along when cruising in the stratosphere at twice the speed of sound.  It could compensate somewhat for that handicap by flying extremely high, at 58,000 feet.  Still, its fuel consumption was outrageous.  (Tennekes, p. 18)

And in the preface, Tennekes writes:

The Concorde went out with a bang.  A fiery crash near Paris on July 25, 2000, signaled the end of its career….In retrospect, the Concorde was a fluke, more so that anyone could have anticipated.  From an evolutionary perspective it was a mutant.  It was a very elegant mutant, but it was only marginally functional.  The fate of the Concorde inspired me to draw parallels between biological evolution and its technological counterpart wherever appropriate.  (Tennekes, p. xii)

Tennekes has more extensive comments on the Concorde in Chapter 6.  At his doctoral thesis defense, he argued “that supersonic airliners would be a step backward in the history of aviation” (p. 165).  He explains that with supersonic flight, the aircraft would have to generate shock waves in the air, which requires “a lot of energy” (p. 166).  On the same page,

Although Concorde passengers didn’t notice anything as their plane penetrated the sound barrier, the economic barrier was real enough.  If you want to exceed March 1, it will cost you 3 times as much as staying below the speed of sound.  For the aircraft industry, supersonic flight was indeed a step in the wrong direction.  Time and again, before aeronautical engineers started dabbling with supersonic flight, they had managed to reach higher speeds and lower costs.  The Concorde broke that trend.

I think it is unfortunate that both Bejan and Tennekes are tempted by the evolutionary metaphor; the critical comments I alluded to in my opening paragraph zero in precisely on this aspect of the work, as well as Bejan’s “constructal law” which he also purports to be at work here.  (I won’t bother to discuss that aspect further.)  Nonetheless the authors are correct that the empirical data and aerodynamic scaling relationships are consistent with each other, and possibly of limited use and interest.  They should not, however, be used to narrow one’s thinking.  For instance, in Tennekes’ plot, a number of animals show up as more severe ‘outliers’ than the Concorde.   Tennekes states that deviations from the trend line may be justified.  The pteranadon, for instance, was a soaring animal.  In prehistoric times there were no polar ice caps, reducing the atmospheric temperature gradient between the poles and equator, compared to today.  As a result there was less wind back then.  He presents other examples, including aircraft.  More generally, just because the bulk of the data fall along a trend line or curve, data away from that trend should not necessarily be deprecated.  Furthermore, correlation should not be confused with causation.  Bejan et al. (2014) offer no such nuances or caveats in their discussion.  Consequently they exaggerate the importance and implications of their findings.

It is also of great concern that Bejan et al. (2014) do not cite, either in the main paper or their supplemental information, Tennekes' work, particularly in the context of the Concorde discussion.  This is unusually poor scholarship.  (Bejan does cite Greenewalt and Pennycuik in an earlier paper, Bejan and Marden, 2006.)  Bejan et al. (2014) also make pointless, tautologous statements such as “Small or large, airplanes are evolving such that they look more and more like airplanes, not like birds” and then in the next paragraph, “Small or large, airplanes are evolving such that they look the same.”  Their abstract ends with the non-sequitur, “The view that emerges is that the evolution phenomenon is broader than biological evolution.  The evolution of technology, river basins, and animal design is one phenomenon, and it belongs in physics.”  Such statements are unjustified, unhelpful, and provide heat rather than light to the discussion.

A technical point should also be made:  at one point, Bejan et al. (2014) comment on their data analysis that “the correlation is statistically meaningful because its P-value is 0.0001, and it is less than 0.05 so that the null hypothesis can be rejected”.  This is a fairly naive and unimpressive statement.  The 0.05 threshold is conventional but totally arbitrary; moreover, the null hypothesis is one of no correlation at all, which is an incredibly low bar to establish a “meaningful” relationship between two variables.  Statistical significance does not necessarily convey practical significance.  For instance, it is possible to make a relationship with a negligibly small slope "statistically significant" if the sample size is large enough.  Reporting any kind of statistical inference (the p-value) on observational, non-randomly sampled data is itself questionable.  Moreover, as Loh (1987) noted, the correlation coefficient does not actually measure the closeness of the data to the best fit line.  The fitted equation and coefficient of determination, which the authors do provide, are more meaningful measures of the strength of the relationship between two variables.  The great statistician John Tukey (1954) stated that "most correlation coefficients should never be calculated."

To conclude, the publication of Bejan et al. (2014) in the Journal of Applied Physics is questionable.  The work should instead have been submitted for review at an aerodynamics or aerospace engineering journal.  I suspect it might not have impressed reviewers in that community.  Moreover, the authors should have cited Tennekes (2009) who provides a more detailed and nuanced discussion of the Concorde case, and they should increase the care with which they interpret correlations in empirical data.  I think the rhetoric about evolution is superfluous and distracting from the authors' primary technical findings, and should have been dispensed with.  Other critics have focused their views on this last point, so I've not dwelt on it here.

References

A. Bejan and J. H. Marden, 2006:  Unifying constructal theory for scale effects in running, swimming, and flying.  Journal of Experimental Biology, 209:  238-248.

A. Bejan, J. D. Charles, and S. Lorente, 2014:  The evolution of airplanes.  Journal of Applied Physics, 116:  044901 (6 pages).

Wei-Yin Loh, 1987:  Does the correlation coefficient really measure the degree of clustering around a line?  Journal of Educational Statistics, 12:  235-239.

Henk Tennekes, 2009:  The Simple Science of Flight:  From Insects to Jumbo Jets.  Revised and expanded edition.  MIT Press (Cambridge, MA).  

John Tukey, 1954:   Causation, regression, and path analysis.  In Statistics and Mathematics in Biology, edited by O. Kempthorne, T. A. Bancroft, J. W. Gowen, and J. L. Lush.  Iowa State College Press (Ames), 35-66.