湖泊水库湖流模拟系统

MATHEMATICAL MODELLING OF LAKE-RESERVOIR CURRENT

在系统研究湖泊、水库各项水动力影响因素的基础上,建立了湖流模拟系统,其中包括水流叠加波浪后波流的共同作用、波浪剩余动量流、风作用剪应力、风吹流以及悬移质扩散分布等。数值模拟中还采用了几种处理技术,并对ADI法进行了双向双步扫描改进。在引滦入津输水工程中的于桥水库湖流计算预报的应用表明,计算结果与现场实测吻合良好,具有计算精度高、收敛快、稳定性好、通用性强等优点。

This mathematical model of lake-reservoir current is based on a thorough understanding of some main factors affecting lake current, and on literature related studies here and abroad, and can be used for detailed research on various hydrodynamics of the reservoir and the action of external loads including the combined action of current and wave, the bottom resistance, the residual momentum of wave flow, the shear stress of wind action, the influance of wind-driven current, the prediction of waves in the reservoir, the transportation and dispersion of sediments, etc.In developing and testing the model, special consideration was given to the energy consumption and decay of the above-mentioned external loads, and to comparison calculations with, and verifications of, several different mathematical models, some unique techniques (including topographies smoothing, overbank flowing, numerical filtering auto-adjusting of roughness in the mathematical model, and modification of ADI method in sweep by two-direction and two-step scanning) were adopted in developing the calculation routines. As a result, this mathematical model has the advantages of high accuracy, quick convergence, good stability and universal adaptability. The routines can be developed and adjusted to form a standard routine for flow pattern calculation for lakes and reservoirs with different external loads and boundary conditions. Calculation results of the model agree well with observed results.The study's overall results, togerther with its calculation hydrologic data for various years, and obtained data on daily wind speed/direction, inflow and outflow rates with or without input from the Luanhe River, transportation and dispersion patterns of suspended load, etc, provide a sound scientific basis for comprehensive conservancy measures for Yuqiao Reservoir.