Videometric water surface tracking: Towards investigating spatial impulse waves

Frederic M. Evers, Willi H. Hager

Thursday 2 july 2015

17:00 - 17:15h at Africa (level 0)

Themes: (T) Special session, (ST) Acoustic monitoring of flow, turbulence and river discharge

Parallel session: 13F. Special session: Acoustic monitoring of flow, turbulence and river discharge

Impulse waves generated by a landslide or other mass wasting events propagate spatially from a locally confined impact zone across the affected water body. Due to the highly dynamic and complex processes related to landslide generated impulse waves, investigations often rely on physical scale models. Conventional wave measurement techniques including point gauges only allow for a limited number of measurement positions in a spatial environment. For tracking spatial elevation profiles of the free water surface within a 3D wave basin a more elaborate approach is required. In this paper, a videometric and therefore non-intrusive technique is introduced for tracking arbitrary water surfaces. With its high density of measurement points, it facilitates the acquisition of a virtually continuous spatial elevation profile of the free water surface. In combination with a hydraulic scale model this measurement technique allows for a detailed study of processes related to the propagation of landslide generated impulse waves. In addition, the techniques presented apply also to other experimental setups in which a precise acquisition of the water surface is of relevance.