【摘要】 为了减小因溃堤洪水而造成的人员生命和财产损失,建立了能够模拟具有实际地形的溃堤水流的数学模型。该模型基于非结构网格的有限体积法,采用HLL格式的近似R iem ann解计算界面通量,并利用TVD-MU SCL格式和H ancock格式将计算精度升高到二阶。对底坡源项采用分解法处理,对摩阻项采用了半隐式离散的方法来增加计算的稳定性。通过溃坝算例和混合流算例,验证了该方法的稳定性、和谐性和健全性。该模型已应用于哈尔滨市松北区溃堤水流的模拟。结果表明,该模型能较好地模拟具有实际地形的溃堤水流运动。更多还原

【Abstract】 Levee-breach water flow in realistic topographies was modeled numerally to reduce the losses of lives and property due to levee breaches.The HLL(Harten,Lax,van Leer) approximate Riemann solver was used to calculate the flow flux using the unstructured finite-volume method.The TVD-MUSCL format and the Hancock format were used to achieve second order accuracy.The divergence form of the bed slope source was used in the model.The semi-implicit approach was used to calculate the friction source terms for a stable calculation.The model was validated with a dam-break case and a classical trans-critical flow case.The results confirm the algorithm’s stability,accuracy and robustness.The model was then used to simulate the levee-breach water flow in the Songbei District in Harbin.The results show that the model accurately simulates levee-breach water flows in realistic topographies.更多还原