Numerical Simulation Research Of Groundwater In Tai'an County,Liaoning Province

Groundwater is the main water supply source of Tai'An.In recent years,the groundwater demand increases with the urbanization acceleration due to the rapid economic development of Tai'An.While the original water supply facilities are far below the water demand,which has become a bottleneck restricting the economic development of Tai'An.It is necessary to increase the exploitation of groundwater resources in order to meet the daily life needs of urban residents.Only if the groundwater resource in Tai'An is analyzed systematically,a reasonable resource evaluation and monitor ing model is established to minim ize the destructive impact on the groundwater resources and environment by the construction projects,achieving more scientif ic and reasonable protection for the groundwater resources and groundwater environment.This paper mainly predicts and studies the flow field of groundwater in Tai 'An after expanded exploitat ion,accordingly the feasibility of groundwater expansion and exploitation is verified and the suggestions of water resources protection measures are proposed,which provides reference basis for the future construction of underground water exploitation and rational utilization of water resources.This paper analyzes the hydrogeology,meteorology,river system,stratigraphic lithology and groundwater movement conditions of Tai'An located in Liao Ning Province.A proper conceptual model of hydrogeological system is established based on the analysis results,and a mathematical model is established,which uses the Visual MODFLOW software to conduct numerical simulat ion calculation.The init ial moment is selected in Apr il 2013 and the ident ificat ion period is 365 d.According to the actual hydrogeological condit ions of Tai'An,the parameters has been adjusted and calculated many times,and the simulat ion program has been operated.The spatial distribution of groundwater flow field is analyzed under the equalizat ion condition and the condition that hydrogeological parameters conform to the pre-set value.In this paper,the flow field at the same period is fitted,and the model established by the experiment is improved by identifying hydrogeologic related parameters,each equalizat ion terms and boundary conditions,which makes it more consistent with the actual hydrogeological conditions of the simulated area.By comparing the fitted values of the measured and simulated flow field,the paper finds that the variation trend of the water-table isohyps is basically consistent in the two curves.When the maximum water level difference between the underground flow field and the measured flow field is compared,this paper finds that the water level difference is less than 0.5m,which shows that the mathematical model established in this paper can accurately simulate the actual situation of underground water flow,at the same time,the mathematical model can be applied to the prediction process of groundwater exploit ation in the research area.In this paper,a 20-year exploitat ion prediction is made to predict the equalizat ion situat ion of the flow field,drawdown and each groundwater compensation supplement at 1,5,10,15 and 20 years respectively.The prediction result shows that,it is feasible to expand the exploitat ion of water source area and there is sufficient supply guarantee.The paper also evaluates the influence of expanding groundwater exploitat ion on regional water resources and geological environment,and the feasibility of the method is also evaluated,which provides a scientific basis for the construction of underground water engineering and the analys is of underground water quality in the future.