Use of Direct Numerical Simulation to Assess the Performance of Acoustic Doppler Technology Characterizing Turbulent Flows

Abstract

This work presents a systematic analysis of the uncertainty associated to spatial and time sampling strategies used to determine flow discharge with acoustic profilers from moving platforms. The study is performed using data sets with high temporal and spatial resolution from direct numerical
simulations of turbulent open channel flow. The simulations results are validated with laboratory scale experimental observations previously reported in the literature. A function of the maximum uncertainty as a function of an appropriately defined measurement time is developed and validated with field scale measurements. The results show that the measurement time is as important as the number of transects performed. The findings of this work are useful tools to define the optimal sampling strategies to perform a good characterization of the flow fields using acoustic profilers.