【摘要】 黄河下游游荡段河床演变情况复杂，是重点关注与治理河段。基于河床滞后响应模型，分别建立游荡段主槽宽度、水深等断面形态参数以及平滩流量的滞后响应模型，并模拟分析主槽宽度与主槽水深、主槽宽度与河相系数、平滩流量与河相系数、流速与河相系数的相互关系。结果表明，不同断面形态参数及过流能力模拟值与实测值变化趋势基本吻合，确定系数与纳什效率系数均在0.80以上，相互关系的模拟结果与实测值变化趋势符合良好。其中：2000年前主槽宽度减小，水深变幅不大，河相系数逐渐减小，平滩流量逐渐减小到最小值，但流速逐渐增大到最大值；2000年后主槽宽度增大，水深增大，但河相系数继续减小，平滩流量虽然逐渐增大，但是流速逐渐减小，相关机理尚待进一步研究。更多还原

【Abstract】 The braided reach of the Lower Yellow River is one to focus on due to its complicated fluvial process. Based on the delayed response model for fluvial processes, the delayed response models for the main channel cross section and discharge capacity adjustment including width, depth and bankfull discharge were established and used to simulate the correlations between main channel width and depth, width and geomorphic coefficient, bankfull discharge and geomorphic coefficient, flow velocity and geomorphic coefficient. The simulation results show that the main channel width, depth and bankfull discharge values of calculated and measured are consistent well which determination coefficient and Nash-Sutcliffe coefficient are higher than 0.80, the simulated correlations are consistent well with the measured results. Of which, before 2000, the main channel width is decreased, but the main channel depth does not change significantly; with the geomorphic coefficient gradually decreases, the bankfull discharge is gradually decreased to the minimum value, but the flow velocity is gradually increased to the maximum value. After 2000, the main channel width and depth are increased, the bankfull discharge is gradually increased, but the geomorphic coefficient continues to decrease, and the flow velocity is gradually decreased. The relevant mechanism needs to be further studied.更多还原