Bedload grains in consecutive meandering bends either move longitudinally or across the channel centerline. This study traces and quantifies the grains’ movement in two laboratorial sine-generated channels, i.e., one with deflection angle θ0 = 30◦ and the other 110◦. The grains originally paved along the channels are uniform in size with D = 1 mm and are dyed in various colors, according to their initial location. The experiments recorded the changes in the flow patterns, bed deformation, and the gain-loss distribution of the colored grains in the pool-bar complexes. We observed the formation of two types of erosion zones during the process of the bed deformation, i.e., Zone 1 in the foreside of the point bars and Zone 2 near the concave bank downstream of the bend apexes. Most grains eroded from Zone 1 are observed moving longitudinally as opposed to crossing the channel centerline. Contrastingly, the dominant moving direction of the grains eroded from Zone 2 changes from the longitudinal direction to the transversal one as the bed topography evolves. Besides, most building material of the point bars comes from the upstream bends, although low-and highly curved channels behave differently.

Li He, D.C. (2021). Experiments on Longitudinal and Transverse Bedload Transport in Sine-Generated Meandering Channels. APPLIED SCIENCES, 11(14) [10.3390/app11146560].

Experiments on Longitudinal and Transverse Bedload Transport in Sine-Generated Meandering Channels

Donatella Termini;
2021-07-16

Abstract

Bedload grains in consecutive meandering bends either move longitudinally or across the channel centerline. This study traces and quantifies the grains’ movement in two laboratorial sine-generated channels, i.e., one with deflection angle θ0 = 30◦ and the other 110◦. The grains originally paved along the channels are uniform in size with D = 1 mm and are dyed in various colors, according to their initial location. The experiments recorded the changes in the flow patterns, bed deformation, and the gain-loss distribution of the colored grains in the pool-bar complexes. We observed the formation of two types of erosion zones during the process of the bed deformation, i.e., Zone 1 in the foreside of the point bars and Zone 2 near the concave bank downstream of the bend apexes. Most grains eroded from Zone 1 are observed moving longitudinally as opposed to crossing the channel centerline. Contrastingly, the dominant moving direction of the grains eroded from Zone 2 changes from the longitudinal direction to the transversal one as the bed topography evolves. Besides, most building material of the point bars comes from the upstream bends, although low-and highly curved channels behave differently.
16-lug-2021
Settore ICAR/01 - Idraulica
Li He, D.C. (2021). Experiments on Longitudinal and Transverse Bedload Transport in Sine-Generated Meandering Channels. APPLIED SCIENCES, 11(14) [10.3390/app11146560].
File in questo prodotto:
File Dimensione Formato  
applsci-11-06560-v2.pdf

accesso aperto

Descrizione: articolo completo
Tipologia: Versione Editoriale
Dimensione 1.46 MB
Formato Adobe PDF
1.46 MB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/10447/531223
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 1
  • ???jsp.display-item.citation.isi??? 2
social impact