实时校正中的旁侧入流反演方法

在水文与水动力学相结合的预报模型中,对于水文模型计算有误差,造成水动力学区间旁侧入流与实际不吻合情况,依据水量平衡原理,对旁侧入流进行反演校正。采用四点线性隐格式求解圣维南方程组,结合卡尔曼滤波技术建立以水位、流量作为综合状态量的卡尔曼滤波状态空间方程。采用反问题的思想把校正后的水位、流量不平衡量反馈到旁侧入流中,修正原有的区间来水量,进而修正预报期的旁侧入流。选择长江干流寸滩至万县河段,以及长江下游大通至镇江段进行演算,分别采用三峡水库135m蓄水阶段的水文资料和1998年水文资料进行6h洪水预报,结果表明旁侧入流反演校正方法是可行的。

Inverse analysis of lateral inflow in real-time correction

In coupling model of hydrology and hydrodynamics,the inaccurate calculation of hydrology model is the cause of the discrepancy between the lateral inflow of hydrodynamics and practical case,so the lateral inflow is updated by using the inverse analysis based on the principle of water balance.With water stage and discharge being state variables,the systematic state equation of Kalman filter is set up based on the Saint-Venant equations solved by the four point linear implicit form.Through the inverse analysis,the unbalance of water stage and discharge are put back to the lateral inflow and adjusted,then the updating water-inflow in forecasting period.The inverse analysis method of the interval inflow is applied to the flow calculation for the river section from Cuntan to Wanxian of the Yangtze River,adopting the flood information of construction period with reservoir storing water as high as 135 m and river section from Datong to Zhenjiang with hydrological information of 1998.The forecast of 6-hour lead time proves that the performance of the inverse analysis method is feasible.