Impacts of Rigid Vegetation on Gravity Currents Propagating in a Stratified Environment
Publication: Journal of Hydraulic Engineering
Volume 149, Issue 12
Abstract
In the stratified environment, systematic experiments are carried out to understand the impacts of rigid vegetation on the evolution of lock–release gravity currents, including the propagation process and entrainment characteristics. A theoretical model is developed to predict the gravity currents completely entering the vegetation-drag-dominated regime and verified by the experimental data. The adjustment of rigid vegetation on the current propagation is limited by the strongly stratified ambient fluid. With the coupling of the stratified ambient fluid and rigid vegetation, responses of current frontal velocity to the change of any single environmental factor are not monotonic. The phenomenon of finger-like intrusion, excited by the stratified environment and promoted by the rigid vegetation, provides a nonnegligible contribution to the current entrainment. In the homogeneous environment, the entrainment occurring in the current head caused by the wakes behind submerged patches is stronger than that of the Rayleigh–Taylor instability, while the situation is reversed when the ambient fluid is stratified.
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Data Availability Statement
All data, models, or codes that support the findings of this study are available from the corresponding author upon reasonable request.
Acknowledgments
This work was partially supported by the National Key Research and Development Program of China (2021YFF0501302), the National Natural Science Foundation of China (52171276 and 41876089), the Key Research and Development Program of Hainan Province (ZDYF2022SHFZ045), and the Science Foundation of Hainan Observation and Research Station of Ecological Environment and Fishery Resource in Yazhou Bay (HNOBYZ2201). This work was also supported by the experimental facility in Nearshore Engineering Hall at ZJU (Zhoushan Campus).
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© 2023 American Society of Civil Engineers.
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Received: Apr 29, 2022
Accepted: Jul 20, 2023
Published online: Sep 26, 2023
Published in print: Dec 1, 2023
Discussion open until: Feb 26, 2024
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