Mobile bed thickness in skewed asymmetric oscillatory sheet flows  

作　　者：Xin Chen Yong Li Fujun Wang 

机构地区：[1]Beijing Engineering Research Center of Safety and Energy Saving Technology for Water Supply Network System, China Agricultural University [2]Tianjin Centre,China Geological Survey

出　　处：《Acta Mechanica Sinica》2018年第2期257-265,共9页力学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China (Grants 51609244, 11472156, and 51139007);the National Science-Technology Support Plan of China (Grant 2015BAD20B01)

摘　　要：A new instantaneous mobile bed thickness model is presented for sediment transport in skewed asymmetric oscillatory sheet flows. The proposed model includes a basic bed load part and a suspended load part related to the Shields parameter, and takes into account the effects of mass conservation, phase-lag, and asymmetric boundary layer development, which are important in skewed asymmetric flows but usually absent in classical models. The proposed model is validated by erosion depth and sheet flow layer thickness data in both steady and unsteady flows, and applied to a new instantaneous sediment transport rate formula. With higher accuracy than classical empirical models in steady flows, the new formula can also be used for instantaneous sediment transport rate prediction in skewed asymmetric oscillatory sheet flows.A new instantaneous mobile bed thickness model is presented for sediment transport in skewed asymmetric oscillatory sheet flows. The proposed model includes a basic bed load part and a suspended load part related to the Shields parameter, and takes into account the effects of mass conservation, phase-lag, and asymmetric boundary layer development, which are important in skewed asymmetric flows but usually absent in classical models. The proposed model is validated by erosion depth and sheet flow layer thickness data in both steady and unsteady flows, and applied to a new instantaneous sediment transport rate formula. With higher accuracy than classical empirical models in steady flows, the new formula can also be used for instantaneous sediment transport rate prediction in skewed asymmetric oscillatory sheet flows.

关 键 词：Mobile bed thickness PHASE-LAG Sediment transport Sheet flow Skewed asymmetric oscillatory flow 

分 类 号：O3[理学—力学]