Bloor, 2011
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David Bloor. 2011. The Enigma of the Aerofoil: Rival theories in aerodynamics, 1909-1930. ~500 pages.
- Topic here: in the early 1900s there were two major schools of thought with theories of lift, one associated with British and the other with German adherents. How did they stay separate for a long time, and then how did they unify?
- Bloor himself is a historian and sociologist of science at Science Studies Unit of U of Edinburgh (p1 etc)
- credits for info and inspiration Takehiko Hashimoto's "The wind tunnel and the emergence of aeronautical research in Britain" and the dissertation on which it was based (p.xi)
- cites Hashimoto, 2000 and 2007 and interactions; lists other topics of Hashimoto, p447: theories of stability, the propeller, scale effects "controversy", the use of graphical methods by engrs, wind tunnel comparisons of the time, and wind-tunnel correction factors
- he spent a lot of time at Max Planck Berlin and with the Royal Aeronautical Society (p.xiii)
- cites useful input from Audrey Glauert, Walter Vincenti, Donald Mackenzie, and many others
- endnotes start on p 447, which explains apparently choppy page numbering below.
- Practical constructors followed trial-and-error methods, and sci and engrs studied the nature of airflow and interaction with objects. (p2) Author does not use the term "tinkerers".
- Early aerodynamics came from hydrodynamics mostly, not from ballistics (p2)
- The math and theory of fluid flow is difficult, so few participated in the field
- Lots of assumptions were needed to calculate flow and effects. Different groups adopted meaningfully different assumptions, and that variation led to the two major schools of thought here. (p2)
- The two main classes of theory to be discussed characterize the flow of air around a wing. They are (1) the discontinuity theory and (2) the circulatory, or vortex, theory, which is the one later accepted.
- characterizes David Hume as a historian and sociologist. Hume like Bloor was in or from Edinburgh. (p3)
- "the force of reason is a social force" (p3) "Education is socialization" and "education is the transmission of [a] culture [by] authority" (p3)
- Re social forces in sci/tech: sci and engrs see themselves as (a) contributing to a certain discipline; (b) members of certain insts; (c) loyal to a tradition or a laboratory; (d) "students of A or rivals of B" (p3)
- "the problem of cognitive order IS the problem of social order" (p4)
- The discontinuity theory was based on work of mathematical physicist Lord Rayleigh, and developed mainly in Britain. The other was proposed by Frederick Lanchester and associated mainly with German engineer Ludwig Prandtl. (p4)
- Early the discontinuity theory had the problem that it predicted only half the observed amounts of lift. (p4) (Could this be related to the Lilienthal error and the Wrights' correction? I suppose not)
- The neglect of Lanchester's theory in Britain became a sort of scandal after 1920 (p5-6)
- The British discontinuity school seemed to dismiss the circulation theory even as they could see the Germans researchers developing (and testing?) it. G.I. Taylor of Cambridge U. was a notable person in this context. Sir Richard Glazebrook, head of Britain's National Physical Laboratory, took the stance that Lanchester's theory was not presented with enough mathematical clarity. Lanchester's life was rich and he was involved in early automobiles; for more see Kingsford, 1960 (p5, p448)
- the term "drift" was standard for "drag" which became standard only after WWI (p447)
- in the U.S. until 1926 there was not significant sci research on the theory of lift, therefore we can leave out the U.S. mostly, and France and Italy too were not central here (p447, endnote 9 which should be in main text)
- Reactions of participants of each school of thought to the other were "symmetric". (p6) (A better term might be "isomorphic," if the forces generating the reaction were internal not the mirroring/reflection of the other.)
- Britain's Advisory Committee for Aeronautics launched around May 1909. It was a a "Whitehall committee" chaired by Rayleigh. Note there was a different ACA in U.S. It became controversial. Its name changed to Aeronautical Research Committee in 1919. Note too the early implication that Rayleigh was both leading the discontinuity school and was influential in determining who the smart insiders of British aeronautics were ; much of the story may simply revolve around him and what he believed. (p6,9)
- Another relevant institution was the Cambridge Mathematical Tripos. (p7)
- Prantdl's school of thought drew from the technische Mechanik or technical mechanics "developed in the German technical colleges. Relevant cities or universities were in Munich, Gottingen, Berlin, and Aachen. (p7)
- The schools reunified with the 1926 publication of Hermann Glauert's textbook The Elements of Aerofoil and Airscrew Theory. Glauert was a brilliant Cambridge mathematician, an Englishman of German descent, who broke from the British discontinuity school and became a determined advocate of the circulation theory. The book covers aerofoils, propellers, airflow, and wind tunnels. (p7)
- Bloor cites Andrew Warwick's Masters of Theory: Cambridge and the rise of mathematical physics as significant for the understanding theories of electromagnetism and the ether of the early 1900s. Some Cambridge Univ mathematicians resisted Einstein's model and Prandtl's in parallel ways. (p8)
- cites Howard T. Wright's Aeroplanes from an Engineer's Point of View (Wright, 1912) (p9)
- "[E]very airplane is to be regarded as a collection of unsolved mathematical problems; and it would have been quite easy for these problems to have been solved years ago, before the first airplane flew." -- G. H. Bryan, Researches in Aeronautical Mathematics, Bryan, 1916 (p9)
- The w:National Physical Laboratory at Teddington, near London, had been founded in 1900, "on the model of Helmholtz's great government-funded institute of physics in Berlin, the w:Physikalisch-Technische Reichsanstalt. (p11)
- A key figure was Richard Burdon Haldane, Britain's secretary of state for war who was a philosopher and fluent in German.
- Haldane had authorized tests on Blair Atoll (Scotland) on a flying machine design of J. W. Dunne. Dunne's craft was intended to be stable. The tests of it in the summers of 1907 and 1908 "failed" (p11-12) Later, Dunne got it working; see Dunne, 1913 in AJ, and Aeroplane 5, 1913 for a diagram. (p450)
- Haldane met the Wrights in early May 1909 on their visit to Britain. He declined to buy their aeroplanes for the British military. (p9-11)
- The British ACA was set up by Herbert Asquith's Liberal administration, and Haldane was an influential figure in creating it.
- Blériot's July 25 1909 flight over the English channel was honored as a major achievement but it also was quickly recognized as a horrifying symbol that Britain was not really safe from the Continent any more. (p9)
Sources
- Author cites many other works on the history of aerodynamic science (p3 and 447)
- See w:Advisory Committee for Aeronautics, w:Richard Burdon Haldane, w:George H. Bryan
Original title | The Enigma of the Aerofoil: Rival theories in aerodynamics, 1909-1930 |
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Simple title | The enigma of the aerofoil |
Authors | David Bloor |
Date | 2011 |
Countries | GB, DE, US |
Languages | en |
Keywords | aerodnamics, aerofoil, lift, military |
Journal | |
Related to aircraft? | 1 |
Page count | |
Word count | |
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