Author(s): B. Sokoray-Varga; T. Kramer; J. Jozsa
Linked Author(s): János Józsa
Keywords: No Keywords
Abstract: Surface PTV technique was implemented in observing and quantifying laboratory dam break flood wave dynamics. Applying a modified version of the velocity gradient tensor (VGT) method the technique handles flows with strong strains. As to error filtering of the raw vector fields, instead of studying the local similarity of the velocity vectors within the same frame, the focus was on the temporal similarity of the velocity vectors in subsequent frames. Flows due to instantaneous dam break on slightly uneven terrain were investigated. In all the investigated cases, one could reasonably track the front propagation, the flow in the immediate breach region, but also the recirculation zones due to flow separation at the edges. The reconstructed velocity field time series offered an insight into the evolution of the flow, and provide a basis for deriving further flow parameters. Parallel to PTV-based flow analysis the data were utilised to validate a quadtreebased, adaptively refined, shock capturing 2D numerical flow model.
Year: 2009