Application of Video Image Analysis for Measurements of River-Surface Flows

Abstract

An image analysis method for the calculation of two-dimensional velocity distributions of river-surface flows is examined. In this method, complicated water surface configurations, which are created by the confliction of boils to the water-surface or by the fluctuation of pressure influenced by turbulence, are considered to be convected with the water surface velocity. Water surface images are taken from the riverside using a video camera. Velocity distributions are calculated by the correlation method after the transformation of images to the non-distorted ones. The application of the method to the Nagara River indicates favorable velocity distribution for the downstream components.