Open AccessStudy on the hydraulic characteristics of the gradually expanding and gradually contracting watercourse with different width-narrow ratios
Author(s) -
Wang Xueting,
Liyun Huang,
Qi Liu,
Zeng Yun
Publication year - 2020
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/794/1/012012
Subject(s) - shearing (physics) , diameter ratio , section (typography) , flow (mathematics) , geology , mechanics , parabola , geometry , geotechnical engineering , physics , mathematics , advertising , business
The characteristics of the water flow in the gradually expanding and gradually contracting watercourse are very complicated, and the width-to-narrowness ratio has a significant influence on the hydraulic characteristics of the gradually expanding and gradually contracting watercourse. Five three-dimensional hydraulic calculation models with different width-to-narrowness ratios were established to study its hydraulic characteristics. The results show that: (1) river flow gradually appears as the recirculation zone with the increase of the width-to-narrowness ratio. The recirculation zone increases gradually with the increase of the width-to-narrowness ratio and the shapes are different. The flow velocity in the recirculation zone is negatively correlated with the width-to-narrowness ratio. (2) When the width-to-narrowness ratio is small, the shearing force distribution of gradually expanding and gradually contracting sections are basically in “Hump-shape” along the Y-axis; When the width-to-narrowness ratio is large, the section basically shows a trend of “parabola-like” change that increases first and then decreases near the shore, and the average shearing force of the expanding section is larger than that of the contracting section. (3) As the width-to-narrowness ratio of the watercourse increases, the shearing force at the widest part of the river section gradually decreases, and the shearing force of the side wall at the contracting section is larger than that of the expanding section.