摘要
为了对小流域洪水设计过程中常用的推理公式法、分布式模型法和地区瞬时单位线法的适用性进行探讨,本文以浙江省宁波市甬江地区水系为研究对象,利用洪峰流量-流域面积比值参数,对设计洪水分别采用3种方法进行计算,然后将各计算结果分别与宁波市洪峰流量100年一遇实测值进行对比分析。研究表明:推理公式法适用于面积小于10km2的流域,其假定条件均与流域的产、汇流条件相符,计算结果更加真实可靠;对于面积大于100km^2的流域,采用不同方法的计算结果与实测结果表现出不同程度的偏差,而分布式模型法的计算准确性相对较高;对于面积为10~100km^2的流域,其坡度较为平缓、河道较长,水动力在空间上可视为均匀分布态,采用地区瞬时单位线法和分布式模型法进行洪水设计较为合理,而后者的计算精确性更好。本文的研究成果有利于提高洪水设计计算法的适用性和准确性,并可为洪水设计方法的选择提供一定的数据支撑和决策依据。
Zhejiang Ningbo Yongjiang water system is adopted as a research object in the paper in order to discuss the applicability of reasoning formula method,distributed model method and regional instantaneous unit hydrograph method commonly used in small basin flood design. Peak flow-basin area ratio parameter is utilized for calculating the designed flood respectively with the three methods. Then,all calculation results are respectively analyzed with peak flow once-in-acentury measured value in Ningbo comparatively. The study shows that the reasoning formula method is suitable for the basins with area less than 10 km^2,the assumed conditions are consistent with the yield and confluence conditions of the basins,and the calculation results are more reliable and truer. The calculation results with different methods have different deviations from the measured results for the basins with area greater than 100 km^2. The distributed model method has relatively high calculation accuracy. The slope is gentler with longer river for the basins with area from 10 to 100 km2,hydrodynamic force can be regarded as uniform distribution in the space, it is more reasonable to adopt regional instantaneous unit hydrograph method for flood design,and the later has higher calculation accuracy. The study results in the paper are beneficial for improving the applicability and accuracy of flood design calculation methods,which also can provide certain data support and derision-making basis for selecting flood design methods.
作者
叶永东
YE Yongdong(Zhejiang Reclamation Construction Group Co.,Ltd.,Ningbo 315040, China)
出处
《中国水能及电气化》
2018年第5期35-40,共6页
China Water Power & Electrification
