ヘリ画像解析と非構造格子浅水流モデルによる実河川洪水流の解析

摘要

River flow structure during flood is one of the most difficult features to capture in river engineering. It is possible to use instruments such as ADCP to measure three-dimensional river flow structures; however, measurement volume or area capable for them to measure is limited to a restricted range. Local remote sensing technique is a good candidate for a wide-ranged river flow measurements. In this research, an aerial survey from a helicopter installed a high definition video (HDV) camera is conduced during a large flood occurred in the Yodo River on September 19 in 2006. From the videotaped flow images, river surface velocity distributions are obtained by PIV by mainly utilizing the movement of specular reflection from surface ripples after the correction of background drift. The measured results are compared with a two-dimensional simulation model based on the unstructured grid system.