Journal of Hydrodynamics

, Volume 30, Issue 6, pp 1045–1054

# Sediment transport in pure acceleration-skewed oscillatory sheet flow

• Xin Chen (陈鑫)
• Fu-jun Wang (王福军)
• Gen-fa Chen (陈根发)
• Liu-chao Qiu (邱流潮)
Articles

## Abstract

In the present study, an analytical concept model is built, using a two-phase model for the sediment transport in a pure acceleration-skewed oscillatory sheet flow. The analytical model is based on the asymmetric wave theory, the irregular boundary layer theory and the exponential concentration distribution theory, to be used for analyzing the phase lag and the boundary layer development related to the acceleration skewness. The two-phase model is applied for the calculations of the instantaneous erosion depth, the sediment flux, the boundary layer thickness and the sediment transport rate, as well as the differences between the positive acceleration stage and the negative acceleration stage caused by the acceleration skewness, as very important in the net current and sediment transport. The effects of the sediment diameter and the phase lag are explained by a comparison with the instantaneous type empirical formula, as is closely related to the acceleration skewness. With the analytical concept model and the two-phase model, the generation of the net sediment transport in the pure acceleration-skewed flows is clearly explained. The phase lag effect is important for the instantaneous sediment transport in the pure acceleration-skewed flow, whereas the boundary layer development difference between the positive acceleration stage and the negative acceleration stage plays a major role in the determination of the net sediment transport.

## Key words

Acceleration skewness analytical concept model boundary layer thickness two-phase model sediment transport rate

## Notes

### Acknowledgement

This work was supported by the Open Research Fund Program of State Key Laboratory of Hydroscience and Engineering of China (Grant No. sklhse-2015-C-03).

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© China Ship Scientific Research Center 2018

## Authors and Affiliations

• Xin Chen (陈鑫)
• 1
• 2
Email author
• Fu-jun Wang (王福军)
• 1
• 2
• Gen-fa Chen (陈根发)
• 3
• Liu-chao Qiu (邱流潮)
• 1
1. 1.College of Water Resources and Civil EngineeringChina Agricultural UniversityBeijingChina
2. 2.Beijing Engineering Research Center of Safety and Energy Saving Technology for Water Supply Network SystemChina Agricultural UniversityBeijingChina
3. 3.China Institute of Water Resources and Hydropower ResearchBeijingChina