開水路乱流の組織的構造に関する実験的研究

Abstract

Pictures of flow patterns in two horizontal cross-sections at different levels near the channelbed were taken successively. They were then digitized and analysed by a computer. Using obta-ined digital data, the distributions of velocity components, vorticity components, streamlines pat-terns, two-dimensional divergence and instantaneous Reynolds stress were calculated and displayed.The idea of a two-dimensional correlation coefficient was introduced to examine convectingprocess, the scale and inclination of turbulence structures.A conceptual model of turbulence structure is proposed, in which characteristics of themultiple structure of turbulence are shown as to the scale and arrangement. Generating mecha-nism of horse-shoe vortices, longitudinal vortices, low-speed streaks, sweeps and ejections are ex-plained based on the model.