Numerical Simulation Study On Karst Water Flow Field In Wangjiahe River Basin Of Central Guizhou

"The ground water is rolling and the surface water is as expensive as oil"is often used to describe the status quo of the central guizhou region,which is threatened by engineering water shortage.With the contradiction between imperfect water conservancy facilities and the increasing demand for water resources due to urban development,engineering water shortage has seriously affected the economic development of central guizhou.This is also a common problem in all karst regions.Therefore,it is urgent and of great practical significance to carry out the hydrogeological research and establish the groundwater model in the central Guizhou.Due to the extreme heterogeneity of the distribution of karst groundwater,the flow characteristics of that are extremely complicated.In order to better simulate the seepage process,the paper proposes the concept of karst pipeline and non-pipeline medium which is suitable for the study area.The model uses karst pipeline to depict the underground river and porous medium to the rock matrix.Through the GMS software combined with the karst pipeline-porous medium coupled seepage model method,the numerical simulation of karst pipeline and non-pipeline groundwater in the Wangjiahe river basin of central Guizhou is carried out,water balance is analyzed and the quantitative analysis of karst groundwater resources is realized,which is to achieve the purpose of making full use of water resources in karst areas.The model calculated after successful verification that the total supply in the study area was 18116.51×10~4 m~3/a.The leakage supply of the watershed in Wangjiahe was the largest source of groundwater supply,accounting for 83.66%;the second source of recharge was the lateral inflow of the boundary,accounting for 11.41%;the recharge of atmospheric precipitation accounted for 4.93%.The total excretion was18116.51×10~4 m~3/a.The discharge of groundwater to the surface water bodies such as rivers accounted for 70%;the second discharge was the lateral outflow of the boundary,accounting for 30%.