Analysisof Time Series of Velocity Fluctuations in a Flow with Vegetative Embayment Using the PTV-Technique

Abstract

Experiments on a river flow are carried out on the basis of PTV-technique to consider the hydraulic characteristics of flows around the vegetative embayment, which is necessary for maintaining or reproducing the function of embayment as a habitat. Though the PTV-method is effective in analysis of the structure at the instantaneous of the flow field, the problem that should be solved about the accuracy still remains to get the long-time velocity information of the flow field. At first, the PTV-measurement is compared for the LDA-measurement in terms of response of particle and the particle tracking area. Next, time series of velocity is estimated from the experimental data of the PTV-measurements, which is analyzed to examine turbulence characteristics that bring about around the vegetative embayment.