4th International Submarine Canyon Symposium (INCISE2018)

5-7 November 2018, Shenzhen, CHINA

View Abstract

This is the detail of Interactions between turbidity current and cyclic steps: a layer-averaged fully coupled numerical case study

< Back to List Version: 1051:1087 Status: Approved Edit Time: 2018/9/30 13:20:17


Author
Peng HU
Co-Author(s)
Yue LI, Chengling Gong
Abstarct Title
Interactions between turbidity current and cyclic steps: a layer-averaged fully coupled numerical case study
Abstarct Body
Here a highly efficient layer-averaged fully coupled model is presented for submarine turbidity currents. Also included is a numerical case study of the interactions between turbidity currents dynamics and cyclic steps in Rio Muni Basin, Equatorial Guinea along West Africa. The present new model is based a previous model by Hu et al. (2012, Journal of Hydrology, 464-465, 41-53). New features include using triangular cells to represent the computational domain, considering non-uniform sediment transport, application of the recently developed local-time-stepping strategy (Hu et al. 2018, Journal of Hydraulic Engineering, under review) to improve computational efficiency. Before applying the model to cyclic steps in Rio Muni Basin, a theoretical analysis is performed with regards to erosion/deposition trends on the velocity-concentration plane. This helps revealing how and to what extent the velocity/concentration has to vary around a bed step, such that inter-change of the erosion/deposition trend could occur in response to an internal hydraulic jump, which is important for migration of cyclic steps. Afterwards, systematic numerical case studies are conducted with regards to turbidity current evolution over the Rio Muni Basin and their effects on bed erosion/deposition. Particular attention is paid to threshold conditions that may lead to the reported erosion/deposition patterns by Li and Gong (2018, Journal of Geophysical Research).
INCISE Theme
Session 2: New ways to study submarine canyons: integrated programmes, new technologies and coordinated monitoring efforts
Presentation Type
Oral Presentation
Keywords
Turbidity current, cyclic step, numerical modeling, sediment transport

< Back to List