No Cover Image

Journal article 509 views 16 downloads

A two-dimensional double layer-averaged model of hyperconcentrated turbidity currents with non-Newtonian rheology

Yining Sun, Ji Li Orcid Logo, Zhixian Cao Orcid Logo, Alistair George Liam Borthwick Orcid Logo

International Journal of Sediment Research, Volume: 38, Issue: 6, Pages: 794 - 810

Swansea University Author: Ji Li Orcid Logo

Abstract

Hyperconcentrated turbidity currents typically display non-Newtonian characteristics that influence sediment transport and morphological evolution in alluvial rivers. However, hydro-sediment-morphological processes involving hyperconcentrated turbidity currents are poorly understood, with little kno...

Full description

Published in: International Journal of Sediment Research
ISSN: 1001-6279
Published: Elsevier BV 2023
Online Access: Check full text

URI: https://cronfa.swan.ac.uk/Record/cronfa64107
Tags: Add Tag
No Tags, Be the first to tag this record!
Abstract: Hyperconcentrated turbidity currents typically display non-Newtonian characteristics that influence sediment transport and morphological evolution in alluvial rivers. However, hydro-sediment-morphological processes involving hyperconcentrated turbidity currents are poorly understood, with little known about the effect of the non-Newtonian rheology. The current paper extends a recent two-dimensional double layer-averaged model to incorporate non-Newtonian constitutive relations. The extended model is benchmarked against experimental and numerical data for cases including subaerial mud flow, subaqueous debris flow, and reservoir turbidity currents. The computational results agree well with observations for the subaerial mud flow and independent numerical simulations of subaqueous debris flow. Differences between the non-Newtonian and Newtonian model results become more pronounced in terms of propagation distance and sediment transport rate as sediment concentration increases. The model is then applied to turbidity currents in the Guxian Reservoir planned for middle Yellow River, China, which connects to a tributary featuring hyperconcentrated sediment-laden flow. The non-Newtonian model predicts slower propagation of turbidity currents and more significant bed aggradation at the confluence between the tributary Wuding River and the Yellow River in the reservoir than its Newtonian counterpart. This difference in model performance could be of considerable importance when optimizing reservoir operation schemes.
Keywords: Double layer-averaged model, Non-Newtonian rheology, Mud flow, Reservoir turbidity current, Yellow River
College: Faculty of Science and Engineering
Funders: This research has been funded by the National Natural Science Foundation of China under Grant No. 12072244.
Issue: 6
Start Page: 794
End Page: 810