基于Flow-3D的水平射流冲刷泥沙数值模拟

摘要

To analyze the whole process of sluice downstream sediment scouring due to horizontal jet, the downstream scouring process of a fixed floor were simulated by using sediment scour model, RNG k-εmodel and FAVOR method in Flow-3D soft-ware and on the basis of the hydraulic model test. The test simulation calculation was carried out according to the conditions of o-riginal hydraulic model. Combining with the result of hydraulic model tests, the water surface profile, velocity distribution, scou-ring hole depth and dune height during the scouring process were compared and analyzed. The result shows that the water surface profile and velocity distribution of the model test and simulation is consistent well, also the simulated scouring hole depth and dune height are in good agreement with the test. The sediment motion is analyzed, and the scouring process in case of different sediment grain size is simulated and the results are compared. It is concluded that the maximum scour depth and dune height de-creases with increase of particle size when the scouring reaches the equilibrium, which is consistent with the theoretical analysis. It is proved that the sediment scouring model can be used in the analysis of variables in hydraulic tests.%为了模拟分析闸口水平射流对下游泥沙冲刷的全过程，基于水工模型试验，采用Flow-3D软件中的泥沙冲刷模型结合RNG 模型和FAVOR方法，进行了水平射流冲刷固定底板下游泥沙的模拟试验。根据原水工模型条件，结合模型试验结果，对冲刷过程中的水面线、流速分布、冲坑深度和堆丘高度进行了对比分析。结果显示，数值模拟与原试验结果中水面线和流速分布吻合度很高，冲刷过程中的冲坑深度与堆丘的高度也很接近。分析了冲刷过程中的泥沙运动，模拟了不同粒径泥沙的冲刷过程并将结果进行对比，发现达到冲刷平衡阶段时冲坑深度与堆丘高度随泥沙粒径的增大而减小，该结论符合理论分析，证明该软件中泥沙模型可用于物理试验中的有关变量分析。