基于和声搜索算法的地下水污染源与未知含水层参数的同步反演研究

Simultaneous identification of groundwater contaminant source and aquifer parameters by harmony search algorithm

地下水污染源反演问题和含水层参数反演问题都是典型的地下水逆问题。在未知含水层参数(渗透系数、弥散度等)等先决信息的情况下进行地下水污染源反演计算时,需要根据已有的监测数据(水位和浓度等)对地下水污染源和未知含水层参数进行同步反演。在同步反演优化问题中,决策变量包括污染源位置、强度以及待求的含水层参数。本文对同步反演模型的框架组成(包括污染物迁移模型和反演优化模型)进行分析后,在对已有的各种和声搜索改进算法进行研究的基础上结合同步反演模型提出一种改进的和声搜索算法,最后将同步反演模型和改进的和声搜索算法应用于具体的算例研究。研究表明,改进的和声搜索算法具有算法稳定高效、求解精度高等特点,能够广泛应用于复杂的地下水污染源和含水层参数反演问题。

Both groundwater contaminant source identification and aquifer parameter identification belong to groundwater inverse problems. In absence of prior information about aquifer parameter, simultaneous identification contaminant source and aquifer parameters are needed on the basis of the obtained monitoring data. In the simultaneous identification problems, the location and strength of contaminant sources, the unknown aquifer parameters are taken as the decision variables. In this paper, the framework of the simultaneous identification model, including simulation model and optimization model, is firstly introduced, and then an improved harmony search algorithm is proposed on the basis of several existing improved harmony search algorithms and combined with the simuhaneous identification model. Finally, the simultaneous identification model, with improved harmony search algorithm, is applied to case study. The case studies indicate that the improved harmony search algorithm is stable and efficient with relative fast convergence speed and the high robustness, and applicable to groundwater contaminant source identification and aquifer parameter identification.