安康水库动库容对水库防洪安全的影响研究

Backwater storage for flood control safety in case of Ankang reservoir

将一维非恒定水力学模型与传统水库调洪演算模型相结合,建立逐时段试算动静库调洪演算模型,并将之应用于安康水库动库容计算和对水库防洪安全的影响分析中。通过采用大型稀疏矩阵非零数据打包存储及消元技术,减小计算机内存占用量,缩短运行时间,提高动静库调洪演算模型的求解效率。通过不同典型和频率洪水的动静库调洪演算对比分析得出:考虑动库容的调蓄作用后,安康水库大多数洪水的调洪最高水位有所降低,动库容对水库防洪安全起正作用;提出了降低控泄流量,提高水库下游安康市防洪标准的动库容防洪安全裕度挖潜措施。还分析了安康水库动库容对防洪安全产生负作用的原因,建议在动库容挖潜利用中慎重考虑该类不利条件。

The paper intends to propose a backwater storage flood muting model to analyze the effect of the backwater storage on the flood control safety in case of Ankang reservoir. The model we have proposed is to combine the one-dimensional unsteady flow model for calculating the in-time reservoir water surface volume with that of the traditional reservoir flood route. For our purpose, we have adopted a partly packed method for the large non-packed, non-synnnetric sparse matrix to store up the non-zero data of the matrix of unsteady flow e- quations along with the elimination method to solve the equations so as to reduce the storage and memory size of the computer and calculation time in the process in hoping to increase the operation efficiency. Comparison of the results of dynamic flood routing with the static flood routing of the different typical floods in addition to the flood frequen- cy, conclusion can be made that the maximum routing water storage level help to facilitate most of the flood control. That is to say, the dynamic storage plays a positive role in the flood safety of the reser- voir for most flood cases. Therefore, it is of the key importance to improve the flood control standard of Ankang city by reducing the controlled outflow from the point of view of the flood resource utilization on the backwater storage. Furthermore, we have also analyzed the mechanism of the negative role in the flood safety of reservoir on the backwater storage in the paper, suggesting that unfavorable utilization of reservoir backwater storage be prevented.