多重岩溶含水介质地下河流量衰减过程实验研究

In Southwest China, there exist abundant karst underground water resources which are important supportive points for local social economic development. The underground river is an important carrier of karst underground water resources. It is the research emphasis for how to use underground river water resources reasonably. Flow attenuation analysis is one of the main approaches in the areas of analyzing flow motion law in karst muti-media, groundwater resources evaluation and identifying hydrological geology characteristics of the aquifer. It has an important role in research significance. It is wrong to pay attention only to application and neglect mechanism research in the flow attenuation field. The research builds physical model of conduit-fissure-pore underground river discharge attenuation. To discuss the factors influencing the discharge attenuation process and more groups of experiments are designed. The factors are sponor, permeability of aquifer medium, the size of the outlet from underground river, rainfall supply situation and initial water condition. Using numerical simulation method to establish the numerical model which fits the physical model structure. The global sensitivity analysis is used to discuss how the model parameters affect the underground river flow attenuation process. The research will provide technical support for studying the flow motion law in karst muti-media and underground water resources evaluation.

我国西南岩溶地区地下水资源丰富，是当地社会经济发展的重要支撑点。地下河作为岩溶地下水资源的重要载体，如何合理利用地下河水资源已成为研究重点。流量衰减分析是分析岩溶多重介质水流运动规律、地下水资源评价和含水层水文地质特征识别的主要研究方法之一，有着重要的研究意义。但目前流量衰减领域存在着重实例应用，轻机理研究的现状。因此本研究拟依托自主研发的多重岩溶含水介质（管道-裂隙-孔隙型）地下河流量衰减物理模型，通过多组控制性实验，分析落水洞、含水介质渗透性、地下河出口大小、降雨补给状态和初始水位状态对衰减过程和衰减系数的影响。同时采用数值模拟方法，建立符合物理模型结构的数值模型，运用全局灵敏度分析法探讨模型参数对地下河流量衰减过程的影响作用。本研究可为岩溶多重介质水流运动规律研究、地下河水资源评价源提供技术支撑。