基于两相浑水模型的三维水沙数值模拟

Simulation of suspended load transport based on two-phase mixture model

本文针对悬移质泥沙输移,采用两相浑水模型进行描述,基于SELFE水动力学模型,尝试通过三维数值格式对两相浑水模型进行探索性模拟.建立了两相浑水模式的离散方程,完善了相应的边界条件,采用多组水槽资料率定并验证了模型的可靠性.并以宁蒙黄河2012年洪水为例,采用离散后的模型对宁蒙黄河青铜峡至石嘴山200 km河段进行了数值模拟.并以该河段洪水的洪峰传播特性、不同河段的环流特性、河段泥沙输移及河床冲淤等为重点关注了改进后的模型.结果表明:计算水位、地形、含沙量等数据与实测资料有较好的吻合,环流特性与理论分析一致.综合表明改善后的模型能很好的应用于悬移质泥沙的模拟.

This paper aims at simulation of suspended load transport through three-dimensional numerical model. Based on the hydrodynamic model of SELFE and two-phase mixture flow, the transport equation is completed and discrete equation with relevant boundary conditions is set up. To verify the new model, different calibration tests are carried, moreover whose results satisfy. Finally, the three-dimensional model is used to study the flood of 2012th year between the Qingtongxia ＆ Shizuishan in Ningxia-Inner Mongolia Yellow River. In addition, this study mainly focuses the character of the flood propagation, circulation features, sediment transport as well as river-bed erosion and deposition. The results reveal that the computed water levels, landform and sediment concentration show good agreement with the measured data. The circulation features are also in accordance with the theoretical analysis. All these indicate that the modified model can effectively simulate the suspended load transport.