Versatile image-based measurements of granular flows and water wave propagation in experiments of tsunamis generated by landslides

Landslides falling into water bodies can generate destructive waves, which can be classified as tsunamis. An experimental facility to study this phenomenon has been set up. It consists of a landslidegenerator releasing gravel at high-speed into a wave basin. A non-intrusive system has been designed...

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Bibliographic Details
Authors: Bregoli, Francesco, Medina Iglesias, Vicente César de|||0000-0001-5578-3848, Bateman Pinzón, Allen|||0000-0001-9980-6554
Format: article
Publication Date:2020
Country:España
Institution:Universitat Politècnica de Catalunya (UPC)
Repository:UPCommons. Portal del coneixement obert de la UPC
Language:English
OAI Identifier:oai:upcommons.upc.edu:2117/183898
Online Access:https://hdl.handle.net/2117/183898
https://dx.doi.org/10.1007/s12650-020-00628-z
Access Level:Open access
Keyword:Granular flow
Tsunamis
Landslides
Particle tracking velocimetry
Image processing
Camera calibration
Granular flow measurement
Landslide tsunami
Video image processing
Wave profile measurement
Materials granulars
Esllavissades
Imatges -- Processament
Àrees temàtiques de la UPC::Enginyeria de la telecomunicació::Processament del senyal
Àrees temàtiques de la UPC::Enginyeria mecànica
Description
Summary:Landslides falling into water bodies can generate destructive waves, which can be classified as tsunamis. An experimental facility to study this phenomenon has been set up. It consists of a landslidegenerator releasing gravel at high-speed into a wave basin. A non-intrusive system has been designed ad-hocto be able to measure the high velocity and the geometry of the landslide as well as the generated waves characteristics. The measurement system employs the treatment of images captured by a high-speed camera which records the launched granular material illuminated by a laser sheet. A grid of laser sheets marks thebasin water surface. The water has been filled by a small amount of kaolin to properly reflect the laser lightat water surface. Thus, by filming with high definition cameras the perturbed water surface and successively processing the resulting images, it has been possible to measure the generated waves. The measurement framework employs a versatile camera calibration technique which allows accurate measurements in presence of: (1) high lens distortions; (2) pronounced non-parallelism condition between camera sensor and plane of measurement coincident with the laser sheet. The maximum resolution of the measurement tool is0.01 mm, while the maximum uncertainty due to systematic error has been estimated to be 15% for theworst-case scenario. This work improves the suitability of image-based measuring systems in granular flows and free surface hydraulics experiments