河道二维数值模拟糙率横向分布研究  

Roughness transverse distribution of plane 2-D flow numerical simulation in river

作　　者：刘臣[1] 平克军[1] 

机构地区：[1]交通部天津水运工程科学研究所工程泥沙交通行业重点实验室

出　　处：《水道港口》2008年第2期113-118,共6页Journal of Waterway and Harbor

摘　　要：糙率是河道对水流阻力大小的描述。文中系统地总结了推求糙率的各种常用方法,分析了糙率沿河道横断面分布的非统一性。采用横断面各个垂线能坡相同的假定原理,利用谢才—曼宁公式,推导出了断面糙率再分配函数。通过点绘多条河流不同河型的不同断面形态的实测水文资料,建立了可应用于平面二维水流数值模拟中阻力沿河宽分布的经验公式,将得到的断面糙率再分配函数应用到对应的河段的平面二维流场数值计算中,计算结果与实测结果吻合良好,解决了计算流速与天然实测流速断面分布不一致的问题,提高了水流二维数值模拟的精度。Roughness is description of flow resistance. The currently used methods for predicting roughness of river channel were studied, the variety of roughness transverse distribution is indicated. It is adopted that the energy slope is fixedness on one section, a function of roughness transverse distribution was gained using the formula of Chezy - manning. Through dealing with a great deal of measured data in several rivers, the experimental formula of roughness distribution along river width adapt to the plane 2 - D numerical simulation of current was deduced. The formula was applied to calculate the velocity field of the corresponding reach along the river, the result shows good agreement with the actual outcome and overcomes the defect of dissimilarity between computed value and observed data of velocity, the computed value of flow field was improved.

关 键 词：糙率 能坡 横向分布 二维数值模拟 流速 

分 类 号：TV148.5[水利工程—水力学及河流动力学] O242.1[理学—计算数学]