基于混合数值解法的二维畦灌地表水流运动模拟Ⅱ:模型验证

A 2-D surface water flow simulation of border strip irrigation based on a hybrid numerical method Ⅱ.Verification

基于典型畦灌试验观测数据和地表水流运动模拟结果,对比分析采用混合数值解法和Roe有限体积法数值求解二维全水动力学畦灌模型在数值计算稳定性与收敛性、计算精度与效率间的差异,验证基于混合数值解法的模型模拟效果。结果表明,混合数值解法要比Roe有限体积法表现出更佳的数值计算稳定性和收敛性,形成的水平衡误差和平均相对误差相对较低,相同度量环境条件下的数值计算效率提高3倍以上。基于混合数值解法的二维全水动力学畦灌数值模型明显增强了数值计算的稳定性和收敛性,有效提高了计算精度和效率,为开展畦灌系统设计与性能评价提供了可靠的数值模拟手段。

The differences of stability convergence,precision and efficiency of the 2-D surface hydrodynamic model for border strip irrigation between the hybrid numerical method pcopased by the authors and the Roe finite volume method,were compared and analyzed based on the observation data of typical border strip irrigation tests.Meanwhile,the computational performance and simulation effect were validated.The results show that the hybrid numerical method exhibits better numerical stability and convergence,and less water quality balance error and average relativity error than the Roe finite volume method.The computational efficiency of hybrid numerical method is about 4 times as much as that of Roe＇s method in the same measurement circumstance.Consequently,2-D strip irrigation numerical model based on the hybrid numerical method can obviously elevate the computational stability and convergence and effectively improve computational precision and efficiency.