摘要
在地表水地下水耦合模拟过程中,源汇项的不确定性会影响模型输出结果的可靠性,故对其进行不确定性分析十分必要。针对一假想算例建立了地表水地下水耦合模拟数学模型,并运用Hydro Geo Sphere软件对其进行同步并行求解。采用Monte Carlo方法分析源汇项的不确定性对于地表水地下水耦合模拟输出结果的影响。在不确定性分析过程中,为减少多次调用模拟模型所产生的计算负荷,采用拉丁超立方抽样和Kriging方法建立模拟模型的替代模型。结果表明:地表水地下水耦合模拟模型能够描述研究区地表水流与地下水流的水力联系;采用Kriging方法建立模拟模型的替代模型,能减少不确定性分析的计算负荷;结合风险评估,地下水水位低于地下水生态水位阈值的风险值为0.2;基于替代模型对地表水地下水耦合模拟模型进行不确定性分析,大幅度地减少了计算成本,为决策者的实际工作提供参考。
In the process of coupling simulation of surface water and groundwater,the uncertainty of source and sink will affect the reliability of the output of the model,so it is necessary to analyze the uncertainty of the model. In this paper,a mathematical model of surface water and groundwater coupling simulation is established for a hypothetical example,and Hydro Geo Sphere software is used to solve it in parallel. Monte Carlo method is used to analyze the influence of uncertainty of source and sink on the simulation results of surface water and groundwater coupling. In the process of uncertainty analysis,in order to reduce the calculation load produced by multiple call simulation models,the replacement model of simulation model is established by using Latin hypercube sampling and Kriging method. Results show that the surface water and groundwater coupling simulation model can describe the hydraulic connection between surface water and underground water in the study area. Kriging method is used to establish an alternative model of the simulation model,which can greatly reduce the computational load of Monte Carlo simulation. Combining with risk assessment,the risk value of groundwater level below the threshold of groundwater level is0.2. Based on the alternative model,the uncertainty analysis of the ground water and groundwater simulation model is carried out,which greatly reduces the cost of calculation and provides a reference for the actual work of the decision-makers.
引文
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