摘要
针对目前泥石流截、排水技术全部采用重力流形式,不仅土石方工程量大、排水效率低,而且泥石流的高挟沙量常常使截排水结构淤积而失效等问题,提出一种具有自清淤能力的水石分离虹吸排水技术.该技术可有效提高泥石流防治的效率和耐久性,虹吸分流池的水动力学特征和清淤能力是该技术能有效实施的基础.应用流体数值软件FLUENT建立三维数值模型,对分流池在虹吸作用下的水力特性进行分析,结果表明:分流池在虹吸作用下产生以虹吸管口为中心的向心速度场;分流池池底切应力与虹吸管径和水头差具有一定的函数关系;虹吸管口至池底面的距离为25%的虹吸管径时池底面的负压水头已具备很强的清淤能力.可以用于指导实际泥石流防治工程的虹吸分流池设计.
The gravity forced technologies are commonly utilized for the cut and drainage of water in debris flows. However, such technologies generally result in large volume of earth works and low draining effi- ciency. Moreover, large carrying sediments in debris flow often deposit the cut drainage structures. There- fore, a debris flow prevention technology which can separate water from debris flow was proposed. The technology can significantly improve the efficiency of prevention engineering and its durability. For such technologies, the hydrodynamic characteristics of shunt pool and dredging ability are the prerequisite. In the present study, a three-dimensional numerical model was proposed to analyze the hydraulic characteris- tics of the pool under the siphon-lift by the FLUENT software. The results reveal that a centriptal velocity field around the siphon pipeis produced due to the effects of siphon in the pool. Besides that, the bed shear stress in the pool is highly associated with the initial siphon head and the siphon pipe diameter. In addi- tion, suction pressure approaches show strong cleansing capacity when the distance from the siphon pipe mouth to the bed is around 25% of the diameter of siphon pipe. The present investigation provides a scien- tific reference for the design of the siphon pool in the practical debris flow prevention engineering.
出处
《浙江大学学报（工学版）》
EI
CAS
CSCD
北大核心
2015年第11期2159-2164,共6页
Journal of Zhejiang University：Engineering Science
基金
国家自然科学基金资助项目(41272336)
关键词
泥石流
虹吸排水
自清淤
池底切应力
debris flow, siphon drainage
self-dredging
bed shear stress
