Ludwig Prandtl ( born February 4, 1875 in Freising, † August 15, 1953 in Göttingen ) was a German physicist. He provided significant contributions to the fundamental understanding of fluid mechanics and developed the boundary layer theory. On him the Prandtl number decreases.
Prandtl (b. Ostermann ) was born as the son of agronomist Alexander Prandtl and his wife Magdalene Prandtl. After attending the Latin School of Freising and Munich Prandtl Ludwigsgymasiums in 1894 began his studies at the Technical University of Munich. After his graduation he became assistant and later the son of the famous mechanic August Foppl. His dissertation, entitled " tipping phenomena, a case of unstable equilibrium" he handed on November 14, 1899 at the Ludwig- Maximilians- University of Munich as a " certified Mechanical Engineer " one. 1900, the doctoral degree he was awarded. He then worked as an engineer in the Maschinenfabrik Augsburg -Nürnberg in the development of factories. When working on an extraction he first came into contact with the fluid dynamics.
He was from 1902 professor at the Technical University of Hanover (now Gottfried Wilhelm Leibniz University ) and resulted in a presentation at the 3rd International Congress of Mathematicians in August 1904, the boundary layer a.
Through support of Felix Klein he taught from September 1, 1904 at the Georg- August-Universität Göttingen. From 1906 to 1908 Theodore von Kármán was his graduate student. Because of his development of the boundary layer theory, he was also in 1909 as Head of the Aerodynamic Research Institute Göttingen (AVA, the predecessor organization of the German Center for Aerospace DLR) appointed. In 1907 he explored the supersonic flow and the resulting shock waves that were predicted theoretically in 1860 by the Göttingen mathematician Bernhard Riemann. In 1908 he built the first wind tunnel in Germany and developed a wing theory that influenced the aircraft. In 1910 he explored turbulent flows and, inter alia, the influence of the later named after him Prandtl number.
Together with Max Michael Munk and Albert Betz, who his successor at the Aerodynamic Research Institute in Göttingen in 1936, he worked on an effective formula for the investigation of buoyancy. In 1919 he produced a significant wing theory, the basis of which it was the first time possible to develop airfoils by means of theoretical studies. Prandtl examined well known as the compressibility of the air at subsonic speeds, also known as Prandtl - Glauert transformation.
From 1920 he worked with Adolf Busemann in a wind tunnel for supersonic flows. In 1929, he developed a method for calculation of supersonic jets, even today, for example, is used in supersonic wind tunnels and rocket engines.
Prandtl from 1925 until 1946 when the director of the Kaiser Wilhelm Institute for Flow Research, which was established thanks to his initiative. During the Second World War, he was in 1942 chairman of the Reich Office research leadership of the Reich Air Minister and Commander in Chief of the Luftwaffe, Hermann Goering was the subordinate. From 1942 he was a corresponding member of the Bavarian Academy of Sciences.
In German-speaking countries, an empirical approximation to the runoff is Prandtl, together with Cyril Frank Colebrook, named with the pipe friction factor ( Prandtl - Colebrook formula, in the English language: Colebrook-White equation).
Prandtl was also a pioneer in the theory of plasticity. According to him, the Prandtl body is a rheological model named.
In his honor, gives the German Society for Aeronautics and Astronautics the Ludwig Prandtl Ring for outstanding merit their own work to the flight sciences in all its disciplines. 1970, a crater on the Moon is named after Prandtl back.
In 1931 his textbook guide to the fluid dynamics, which was from the beginning as the standard work of fluid mechanics. The Prandtl was later constantly updated by renowned scientists and flow 2007 is available in the current 11th edition of 2002.