The Laminar Boundary-Layer Equations. I. Motion of an Elliptic and Circular Cylinders

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DOI: 10.1098/RSPA.1948.0026

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摘要: The main results obtained are as follows: (a) problem is reduced, for the front part of a cylinder, to non-linear differential equation same form that studied by Falkner & Skan (1930), namely, f$^{\prime \prime \prime}$ + ff$^{\prime = $\lambda $(1 - 2}$). This has been numerically solved Hartree (1937), so evaluation velocities and surface friction requires only very simple short computations. Near separation point leads more complicated (3$\cdot $20). (b) Elliptic cylinder. calculated observed agree up including x 1$\cdot $457 (section 5), where distance along boundary ellipse from forward stagnation point, expressed multiple minor axis. An approximate integration, neglecting certain terms in $20), gives at about 108 degrees 30$^{\prime}$ against 103 observed, angle corresponds elliptic co-ordinate (4$\cdot $1). (c) Circular In all cases shows good agreement with results, previously experimental pressure distributions, case cylinder diameter d 5$\cdot $89 in. (by $20)) show observations almost point. (d) Pressure consists two terms: one equal potential flow, other depends on thickness layer.

参考文章(5)
Sydney Goldstein, Modern developments in fluid dynamics ,(1938)
Ludwig Prandtl, Albert Betz, Vier Abhandlungen zur Hydrodynamik und Aerodynamik Göttinger Klassiker der Strömungmechanik. ,(2010) , 10.17875/GUP2010-106
N.A.V. Piercy, J.H. Preston, L.G. Whitehead, LXX.The approximate prediction of skin friction and lift The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science. ,vol. 26, pp. 791- 815 ,(1938) , 10.1080/14786443808562173
K. Pohlhausen, Zur näherungsweisen Integration der Differentialgleichung der Iaminaren Grenzschicht Zamm-zeitschrift Fur Angewandte Mathematik Und Mechanik. ,vol. 1, pp. 252- 290 ,(1921) , 10.1002/ZAMM.19210010402
D. R. Hartree, On an equation occurring in Falkner and Skan's approximate treatment of the equations of the boundary layer Mathematical Proceedings of the Cambridge Philosophical Society. ,vol. 33, pp. 223- 239 ,(1937) , 10.1017/S0305004100019575