论文部分内容阅读
为研究冲积河流平滩流量的变化规律,以黄河下游1950—2007年实测水沙及平滩流量数据为基础,根据量纲和谐原理,建立了反映冲积性河流河床演变规律的驱动与响应模型。对驱动与响应模型中水沙驱动力进行了小波分解;通过小波方差求极值的方法,确定了水沙驱动力的主要时间尺度;并利用主要时间尺度下对应的周期函数代替了驱动与响应模型中的水沙驱动力。进而通过积分运算得出平滩流量驱动与响应模型的解析解。结果表明:黄河下游水沙驱动力具有4—5a和19—20a主要时间尺度;应用到黄河下游5个主要测站具有较好的计算结果。
In order to study the variation regularity of flat beach flow in alluvial river, based on the data of measured sediment discharge and flat beach discharge from 1950 to 2007 in the lower reaches of the Yellow River, a driving and response model reflecting the evolution of alluvial river bed was established according to the principle of dimension harmony. Wavelet decomposition of driving forces in the driving and response model was carried out. The main time scale of driving forces for water and sediment was determined by the wavelet variance and the corresponding periodic function of the main time scale was used to replace the driving and response Water and sand driving force in the model. Then the analytic solution of flat-beach flow-driven and response model is obtained through integral operation. The results show that the driving forces of water and sediment in the lower Yellow River have the main time scales of 4-5a and 19-20a, and the five main stations applied to the lower Yellow River have good results.