基于GIS泥石流二维数值模拟

为了模拟泥石流的运动规律，预测降雨诱发的泥石流到达距离和泛滥范围，减少和避免泥石流引起的灾害，给出了一个模拟泥石流运动的二维数值模型。由于GIS中的栅格网络数据可以直接作为有限差分的网格，二维数值模型可用有限差分来求解。模型应用于2003年7月20日发生在日本九州南部熊本县水俣市宝川区集村的泥石流。模拟再现了这个真实泥石流的传播和泛滥的过程，并与实际检测结果很吻合，验证了这个深度积分的二维数值模型的有效性和实用性。模型可用于预测泥石流的流动距离和泛滥范围，以及泛滥范围内的危险房屋和路段，也可以用于泥石流灾害的风险性分析。

GIS-based two-dimensional numerical simulation of debris flow

To predict the run out distance and extent of the hazard area of rainfall-induced debris flows, we proposed a depth-averaged two-dimensional numerical model, in which the debris and water mixture is assumed to be a uniform continuous, incompressible, unsteady Newtonian turbulence fluid. As raster grid networks of digital elevation model in GIS can be used as the finite difference mesh, the continuity and momentum equations are solved numerically using the finite difference method. All the input data and output are processed in GIS. The model is applied to simulate the rainfall-induced real debris flow of July 20, 2003, in Minamata City of southern Kyushu, Japan. The simulation reproduces the propagation of the real debris flow; and the results are in good agreement with the field investigation. The two-dimensional numerical simulation using GIS can be used to estimate the potentially inundated areas, the potentially dangerous homes and roads for hazard and risk analysis.