Comprehensive numerical simulation for prediction of long-term hydrologcal environment

为了找到预测地表和地下流体长期动态的有效方法，研究了综合建模方法，构建了综合仿真系统。以下是本研究的总结。(1)为了全面模拟水文过程，提出了地表水流与地下多孔介质水流的耦合处理方法。将曼宁定律表示的表面流体流动与多孔介质中的两相达西流动相结合。(2)为了处理多孔介质中的质量输运现象，建立了一个包含转换/扩散、流体之间的质量交换、流体与岩石之间的吸收和解吸的三相、三组分流体系统的一般方程组。(3)将传热纳入综合多相方程，将流体和岩石的温度分别处理，以表达多孔和裂隙岩石中的热流。(4)建立了综合考虑地表/地下多相流体对流/扩散和热量的水文三维数值模拟系统。编写了用于处理输入数据和输出演示的图形系统。(5)对所开发的仿真系统进行了实验研究和数值模型研究。进行了不同类型的场尺度模拟。其中包括大型储油岩洞周围流体行为的水文评价研究、有机溶剂污染地下水、地下水温度随入流温度季节变化的预测以及大规模降雨径流模型。

For the purpose of develping useful measure for predicting long term behavior of fluids on surface and in subsurface, comprehensive modeling methods were studied and a comprehensive simulation system was constructed. The followings are the summary of this study.(1) To model hydrological process totally, coupled treatment of surface water flow and the flow through porous media in subsurface, was proposed. Flow of surface fluid expressed by Manning's law was combined with the 2-phase Darcian flow throygh porous media.(2) To treat mass transport phenomena in porous media, a general system of equations expressing 3-phase, 3-component fluid system was developed, in which converction/diffusion, mass exchange among fluids, absorption and desorption between fluid and and rock, are included.(3) Heat transfer is included in the comprehensive multi-phase equations, in which temperatures of fluid and rock are treated separately in order to express the thermal flow in porous and fractured rock.(4) A comprehensive hydrological 3-D numerical simulation system that incorporates multi-phase convection/diffusion of fluids and heat in surface/subsurface, was developed. Graphic system for handling input data and output presentations was prepared.(5) Several experimental studies and numerical model studies were done to validate the developed simulation system. Various types of field-scale simulations were made. They include the hydrological evaluation study of fluid behavior around large rock caverns for oil storage, groudwater pollution with organic solvent, prediction of groundwater temperature with the seasonal change in inflow temperature, and a large-scale rainfall-runoff modeling.