Discharge measurement using Large Scale PIV under varied flow conditions - Recent results, accuracy and perspectives

摘要

For 10 years now, Large Scale Particle Image Velocimetry (LSPIV), an image-based method, has been increasingly used for non contact rivers survey. LSPIV is a statistical identification of displacement flow from images on natural scale of rivers. This includes measurements of surface velocity distribution and discharges for very different sizes of rivers with sections as small as few meters and as large as hundreds of meters, without and with seeding of the flow, and with different sensing systems. This presentation is a review of a number of experiments, using the LSPIV method, conducted those last 10 years under varied flow conditions, I.e. from low flow to high flow. The authors present results of those experiments and highlight the advantages and weaknesses of the LSPIV measurements. The authors also present recent collaborative work between IIHR-Hydroscience & Engineering, Iowa City, USA and the Laboratoire d'etude des Transferts en Hydrologie et Environnement (LTHE), Grenoble, France. Those include measurements (ⅰ) from a mobile LSPIV platform, I.e. a truck-based system and (ⅱ) from a permanent location at the Iowa River, where continuous real-time estimations of the discharge are performed. The authors present results of those experiments and highlight the advantages and weaknesses of the LSPIV measurements in field conditions.