Von Karman, Theodore

Karman, Theodor von (1881—1963). Hungarian scientist who worked in Germany the US on aeronautical problems, on rockets, and on combustion phenomena Ref Anon, Explosivst 1963, 134... 

While fishing in Transylvania, Theodore von Karman noticed that downstream of the rocks the distance between the shed vortices was constant, regardless of flow velocity (Figure 3.104). From that observation evolved the three types of vortex meters the vortex shedding, the vortex precession, and the fluidic oscillation (Coanda) versions. All three types detect fluid oscillation. They have no moving components and can measure the flow of gas, steam, or liquid. 

The boundary layer concept is attributed to Ludwig Prandtl (1874—1953). His manuscript, published in 1904, formed the basis for the future work on skin friction, heat transfer, and fluid separation. He later made original contributions to finite wing theory and compressibility effects. Theodore von Karman and Max Munk were among his many famous students. 

When a fluid flows past a bluff body, the wake downstream will form rows of vortices that shed continuously from each side of the body as illustated in Figure 4.16. These repeating patterns of swirling vorticies are referred to as Karman vortex streets named after the fluid dynamicist Theodore von Karman. Vortex shedding is a common flow phenomenon that causes car antennas to vibrate at certain wind speeds and also lead to the collapse of the famous Tacoma Narrows Bridge in 1940. Each time a vortex is shed from the bluff body it creates a sideways force causing the body to vibrate. The frequency of vibration is linearly proportional to the velocity of the approching fluid stream and is independent of the fluid density. 

Theodor von Karman (11 May 1881-7 May 1963), smdied 1898-1902 in Budapest, and 1906-1908 in Gottingen, Ph.D. 1908 became Privatdozent in Gottingen in 1910, and was then professor of mechanics (as successor to Arnold Sommerfeld) and aerodynamics at the Aachen T.H. (1913-1933). He became director of the Guggenheim Aeronautical Laboratory at the California Institute of Technology in Pasadena from 1933 to 1949, where, with his theory of turbulence, he fostered the development of modem variable swept-wing aircraft. 

At Johns Hopkins Clauser established the Department of Aeronautics. He pubUshed widely in the fields of aerodynamics, of non-linear meehanies, fluid dynamies and on the reduetion of combustion engine emissions. His 1937 PhD thesis deals with the cmwature effect on the transition from laminar to turbulent boundary layers, a topie in which his tutor Theodor von Karman (1881-1963) was interested since deeades. The result was applied to flows over the upper surface of a wing. The discrepancy between the predieted and the actual transition point was due to the effect of streamline emwature, which may become relatively large due to the relatively small wing curvature radius. 

Vetterling William T., 370 Vila Jorge A., 819 Vinh Josiane, 469 Vohra Yogesh K., 948 Volterra Vito, 971, 980 von Karman Theodore, 524 von Neumann John... 

Karman vortex street A phenomenon in which vortices of a moving fluid form as repeating patterns. They are caused by the unsteady separation of flow of a fluid as it passes around an object such as a wire and observed over Reynolds numbers of around 90. It is named after Hungarian-American mathematician and physicist Theodore von Karman (1881 -1963) and is also known as the von Kton n vortex street. 

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