倾斜岸坡角形域顶点排污浓度分布规律探讨  

Study on orderliness of concentration distribution of contaminants discharged into corner field from effluent intersection of gradient bank

作　　者：武周虎[1] 徐美娥[1] 武桂芝[1] 

机构地区：[1]青岛理工大学环境与市政工程学院,山东青岛266033

出　　处：《水力发电学报》2012年第6期160-165,197,共7页Journal of Hydroelectric Engineering

基　　金：国家自然科学基金资助项目(50979036;50839001)

摘　　要：基于镜像法原理和角形域平面镜映射实验,给出了横向与垂向扩散系数不相等的角形域θ=360°/β(β为奇数)映射图。从无限区域静止水体中瞬时线源的二维扩散和等强度连续点源三维移流扩散简化方程的解析解人手,分析推导出角形域顶点排污瞬时线源扩散的浓度近似计算公式,进而得到了角形域顶点排污等强度连续点源移流扩散浓度分布的理论公式。结果分析与讨论表明,在简化条件下该理论公式与可对比理论解完全一致,角形域内角角度对污染物的浓度分布影响很大,呈现出以角域映射系数β=4的倍数的周期性变化规律,角形域顶点排污浓度分布具有复杂性和多重性。该理论公式可为水库岸边污染混合区浓度估算提供有力的工具,适用条件为顺直倾斜岸坡大宽度深水情况,满足内角θ=360°/β的角形域顶点排污浓度的近似计算。This paper presents a mapping graph of corner field θ=360°/β（β is an odd number） featured by different coefficients of transverse and vertical diffusion on the basis of an experiment of plane mirror mapping and the mirror image theory.Starting from an analytical solution to the simplified equations of 2-D diffusion of instantaneous line source in an infinite still water body and 3-D advection-diffusion of a uniformly-distributed continuous line source in a corner flow field,we established an approximate formula of concentration calculation for the 2-D diffusion of the instantaneous line source discharged into the corner flow,and then derived an analytical formula for 3-D advection-diffusion of the continuous line source discharged into the corner flow.The results show that this analytical formula agrees well with the theoretical solution compared.The interior angle of the corner field has great influence on the distribution of pollutant concentration,and this distribution takes orderliness of a periodicity that is a multiple of the corner field mapping coefficient β=4,showing complexity and multiplicity of the distribution pattern.The analytical formula is very useful for estimation of pollutant concentration in the near-bank mixing zone of reservoir,and its applicable conditions are a wide and deep water body near a gradient bank with a planar surface which satisfy θ=360°/β.

关 键 词：环境水力学 倾斜岸坡 角形域 浓度分布 周期性规律 镜像法 

分 类 号：X143[环境科学与工程—环境科学] X524