Print Email Facebook Twitter A laboratory and numerical study of transverse momentum exchange in vegetated channels Title A laboratory and numerical study of transverse momentum exchange in vegetated channels Author Truong, S.H. (Korea Institute of Civil Engineering and Building Technology; Thuyloi University) Li, Un (Korea Institute of Civil Engineering and Building Technology) Uijttewaal, W.S.J. (TU Delft Environmental Fluid Mechanics) Contributor Uijttewaal, W. (editor) Franca, M.J. (editor) Valero, D. (editor) Chavarrias, V. (editor) Arbos, C.Y. (editor) Schielen, R. (editor) Crosato, A. (editor) Date 2020 Abstract Transverse exchange processes of mass and momentum in floodplain regions of channels are of primary importance regarding the sediment transport and riverbank stability. The presence of large horizontal coherent structures (LHCSs) at the interface of the floodplain and main channel regions may contribute up to 90% the amount of transverse momentum exchange between these areas. Although many momentum exchange models have been proposed and developed, their applicability in different circumstances is still unclear as their validity is usually restricted to a narrowly ranging experiment data set. In order to obtain more insight, two unique laboratory experiments of a shallow flow field in a floodplain channel with and without vegetation have been conducted. One small scale experiment was conducted at the TU Delft Water Lab. Another large-scale experiment of floodplain vegetated channel has been conducted at the Korea Institute of Civil Engineering and Building Technology -River Experiment Center (KICT-REC). The experimental data has been used to verify state-of-the-art momentum exchange models. As the limitations of these models were analyzed, a new eddy viscosity model based on the occurrence of LHCSs was proposed and validated using a variety of experimental data sets. A numerical model mimicking physical models was constructed. The experimental results were compared with the numerical results, showing the capacity of the new eddy viscosity model. Furthermore, the experimental results confirm the presence of LHCSs in a large-scale experiment. The LHCSs have the length of about 15m, which is one order of magnitude larger than that observed in the small-scale experiment. Subject Vegetated channelexperimentlarge coherent structuresnumerical model To reference this document use: http://resolver.tudelft.nl/uuid:65582f95-a5b4-425e-8271-aaddfac550fb Publisher CRC Press / Balkema - Taylor & Francis Group, London Embargo date 2021-02-27 ISBN 978-0-367-62773-7 Source River Flow 2020: Proceedings of the 10th Conference on Fluvial Hydraulics (1st) Event River Flow 2020, 2020-07-07 → 2020-07-10, Delft, Netherlands Bibliographical note Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public. Part of collection Institutional Repository Document type conference paper Rights © 2020 S.H. Truong, Un Li, W.S.J. Uijttewaal Files PDF A_laboratory_and_numerica ... annels.pdf 1.2 MB Close viewer /islandora/object/uuid:65582f95-a5b4-425e-8271-aaddfac550fb/datastream/OBJ/view