论文标题
使用不连续的Galerkin解决方案进行浅流速速度预测
Shallow-flow velocity predictions using discontinuous Galerkin solutions
论文作者
论文摘要
二维(2D)浅水方程(2D-SWE)的数值求解器可以是预测准稳态流中或整个液压工程结构中速度场的空间分布的有效选择。二阶有限体积求解器(FV2)假动地在其预测中延长了小规模的循环涡流,除非由人造涡流粘度维持,而三阶有限体积(FV3)求解器可能会在其预测中扭曲eddies。二阶不连续的Galerkin(DG2)求解器中的额外复杂性导致误差耗散显着降低,并在更粗的分辨率下改善了预测,这使其成为浅水流中速度预测的可行竞争者。本文通过参考FV2或FV3求解器分析了基于网格的开源DG2求解器的这种预测能力,以在子米尺度上模拟速度幅度和方向。针对四个实验测试用例的测量速度数据评估了模拟预测。结果始终表明,DG2求解器是有效地产生更准确的速度分布的竞争选择,用于以平滑流动区域为主导的模拟。
Numerical solvers of the two-dimensional (2D) shallow water equations (2D-SWE) can be an efficient option to predict spatial distribution of velocity fields in quasi-steady flows past or throughout hydraulic engineering structures. A second-order finite volume solver (FV2) spuriously elongates small-scale recirculating eddies within its predictions, unless sustained by an artificial eddy viscosity, while a third-order finite volume (FV3) solver can distort the eddies within its predictions. The extra complexity in a second-order discontinuous Galerkin (DG2) solver leads to significantly reduced error dissipation and improved predictions at a coarser resolution, making it a viable contender to acquire velocity predictions in shallow flows. This paper analyses this predictive capability for a grid-based, open source DG2 solver with reference to FV2 or FV3 solvers for simulating velocity magnitude and direction at the sub-meter scale. The simulated predictions are assessed against measured velocity data for four experimental test cases. The results consistently indicate that the DG2 solver is a competitive choice to efficiently produce more accurate velocity distributions for the simulations dominated by smooth flow regions.