进口流速对丁坝回流长度影响的数值模拟研究

Study of numerical simulation on influence of inlet velocity on recirculation scale

运用计算流体力学(CFD)方法,对宽浅河道中非淹没丁坝的流场进行二维数值模拟研究。模拟结果显示RNG k-ε模型能够较好地描述出丁坝下游实际回流特征的产生,扩散及消失过程,能够较好地模拟丁坝下游的回流尺度。最后采用此模型模拟不同进口流速在相同条件下的流场结构,通过量纲分析与数值模拟结果的比较分析得到进口流速对回流尺度影响的关系式。进口流速越大,回流边线越长越宽。研究结果对丁坝的设计与施工,具有一定的参考意义。

The method of computational fluid dynamics （CFD） was used to carry out numerical simula- tion study to 2D flow field in wide and shallow region with a non-submerged spur-dike. The simulation re- suits show that the RNGk - ~ model can better describe the actual water characteristics around spur - dikes, the recirculation diffusion and disappearing process, and simulate the recireulation scale. The flow structures with different inlet velocities under the same conditions were simulated with the model. Through dimensional analysis and comparative analysis of numerical simulation results, the paper got the relation of inlet velocity and recirculation scale. The larger the inlet velocity, the longer and wider the re- circulation sideline. The research result has a certain reference significance for the design and construc- tion of spur-dikes.