30 research outputs found

    The Microstructure of Turbulent Flow

    Get PDF
    In 1941 a general theory of locally isotropic turbulence was proposed by Kolmogoroff which permitted the prediction of a number of laws of turbulent flow for large Reynolds numbers. The most important of these laws, the dependence of the mean square of the difference in velocities at two points on their distance and the dependence of the coefficient of turbulence diffusion on the scale of the phenomenon, were obtained by both Kolmogoroff and Obukhoff in the same year. At the present time these laws have been experimentally confirmed by direct measurements carried out in aerodynamic wind tunnels in the laboratory, in the atmosphere, and also on the ocean. In recent years in the Laboratory of Atmospheric Turbulence of the Geophysics Institute of the Soviet Academy of Sciences, a number of investigations have been conducted in which this theory was further developed. The results of several of these investigations are presented

    Radio scintillation of gamma-ray-burst afterglows

    Get PDF
    Stars twinkle to the eye through atmospheric turbulence, but planets, because of their larger angular size, do not. Similarly, scintillation due to the local interstellar medium will modulate the radio flux of gamma-ray-burst afterglows and may permit indirect measurements of their angular sizes. The amplitude of refractive scintillation is of order ten percent at ten gigahertz unless the source size is much larger than the expected size, of order ten microarcseconds. Diffractive scintillation is marginally possible, depending sensitively on the source size, observing frequency, and scattering measure of the interstellar medium.Comment: 11 pages, LaTeX2e, requires elsart.cls. Submitted to New Astronom

    Multiple Laue-Spots from Aluminum Crystals

    Full text link
    corecore