最高冰塞,冰坝水位计算与预报的动力—随机模型

应用动力模型可以计算出某一流量过程的最高冰塞、冰坝水位。然而在设计工作中希望知道在某一概率流量情况下的最高冰塞、冰坝水位。为此，本文建立了相应的动力－随机模型。据本文作者所知道的情况，该模型在文献中尚未见到过。本文用水动力学及随机函数的相关理论两种方法论证了动力－随机模型解的收敛性。在该模型中本文建议用数学期望作为边界断面的时均值，用均方差作为边界断面上的随机值。在最大流量概率密度服从对数正态分布

A Dynamic-Stochastic Model for Calculation and Forecast of Maximum Ice Jam Stages

The dynamical model can be used to calculate maximum ice jam stages when discharge hydrographs at boundary sections are provided. However, maximum ice jam stages corresponding to a given probability exceeding are usually necessary in project practice. For this purpose a dynamic-stochastic model has been established in this paper. So far as thewriter of this paper is aware that the developed model is not available yet in recent literature. The convergence of solution to the dynamic-stochastic model is proved both by means of hydrodynamics and by using the correlation theory of stochastic function in this paper. In the model mathematic expective value and mean square error of a stochastic process have been recommended as the average value with time and the stochastic value at boundary sections respectively. Under the condition of a series of real maximum discharges during winter period being assumed to obey to Log-normal distribution the discharge of a given probability exceeding can be computed through use of a certain transformation. After substituting obtained discharges by this way into the dynamic model as boundary values the maximum ice jam stages corresponding a given probability exceeding will be calculated. The prospect for further utilization of the developed model is great. It may be used to calculate velocity fluctuation, pulsation of thermal flux and ice discharges as well to determine errors of calculation characteristics caused by some external stochastic factors.