Study On Numerical Simulation Of Groundwater In Jinan Spring Area Based On MODFLOW And Evolutionary Algorithm

There are so many famous springs which are known to the world because of the unique natural landscape and history in Jinan city.The water resources in Jinan spring area play a very important role in promoting the development of urban economy,maintaining the characteristics of urban landscape and ensuring the harmonious life of the people.However,due to the reasons like development of urban economy,the acceleration of urbanization,the expansion of urban scale and the huge population,the contradiction between groundwater resources and human society development in water resource demand has become increasingly prominent.Therefore,it is important to construct the numerical model of groundwater in Jinan spring area to study the sustainable development and optimal allocation of groundwater resources in Jinan.Based on relative research in world and Jinan natural geography,socio-economic,hydrogeological conditions and water resources utilization,this paper organized the original data of Jinan spring area and the simulation range of the study area is determined.According to the real situation of the study area and the source and sink items,the concept model of groundwater in Jinan spring area was established.In order to solve the problem,the main parameters of the aquifer was analyzed by coupling the evolutionary algorithm with the MODFLOW program using the data such as measured data like hydrogeology,meteorology,water resources utilization and observation well water level.Time from October 1,2012 to September 30,2013 as the model of the simulation identification period,October 1,2013 to September 30,2014 as the model validation period to determine the reliability of the model,and the results of evolutionary algorithms in the practical application of aquifer parameters are discussed in the end.The conclusions are drawn as followings:(1)According to the data analysis and field investigation,268 effective drilling holes were extracted from the study area,and the conceptual model and mathematical model of Jinan spring domain hydrogeology were established.(2)The fast and harmonious search algorithm for model parameters was first applied to Jinan,To overcome the disadvantages of manual manual tuning in the past and the lack of capacity of traditional evolutionary algorithms in global optimization;(3)The evolutionary algorithm is coupled with the MODFLOW program to solve the problem of the groundwater model which solves the difficult problem of the model in the case of incomplete data,and saves the time required for numerical solution under the premise of satisfying the accuracy of the model.(4)The simulated value is about 45% of the node with the deviation of the observed value less than 0.5m,and the node is about 30% between 0.5m and 1m.The calculated value of the water level is basically the same as the observed water level in the time series trend,Which further validates the application prospect of the optimization algorithm in the field of hydrogeology,which can provide strong support for the establishment of Jinan spring domain optimization management model.