大規模乱流構造の可視化と解析 (2)

Abstract

Tracer method was applied to take the time series of pictures of flow patterns in horizontalcross-sections of an open channel flow. The pictures obtained were processed by a computersystem. The method of experiment and analysis reported in the foregoing report was revisedwidely to get more precise results.Various kinds of physical properties of the flow in horizontal cross-sections such as distributionof velocity vectors, two-dimensional divergence and patterns of streamlines, time-lines and path-lines were evaluated numerically and they were displayed as graphical outputs. At the same time, vertical components of velocity vectors were evaluated on the assumption of the frozen turbulence.These results contributed to the elucidation of the three-dimensional structure of turbulentopen-channel flows such as low speed streaks, upflows, downflows, bursts and downrushes.