某工程溢洪道掺气水流流场数值模拟研究

Research on the Numerical Simulation of the Flow Field of Aerated Water Flow in the Spillway of a Project

为研究不同数学模型模拟溢洪道内掺气水流的情况,利用CATIA软件建立某实际工程三维几何模型并导入FLOW-3D软件中,采用卷气模型对溢洪道流场进行数值模拟,利用ICEM软件对模型修改得到计算所需流体域,基于VOF模型和欧拉双流体模型,利用FLUENT软件分别对溢洪道内的掺气水流进行三维数值模拟。结果表明,三种模型的计算流态和流速结果差别较小,与物理模型试验结果基本吻合;对于压强分布,卷气模型计算结果与模型试验结果吻合较好,而VOF模型和欧拉模型的计算结果误差较大;对于紊动能分布,欧拉模型和VOF模型的计算结果基本一致,但与卷气模型的计算结果相比差异较大;对于溢洪道中心线底部掺气率,卷气模型和VOF模型计算结果不合理,欧拉模型的计算结果符合实际情况。该研究结果可以为掺气水流计算和工程设计提供参考。

In order to study the aeration with different mathematical models in spillway,the CATIA software is used to establish three-dimensional geometric model of an actual project,and it is introduced into FLOW-3D.The air entrainment model is used to conduct the numerical simulation of the flow field of the spillway.The fluid domain of spillway is obtained by modifying the model through ICEM.Based on the VOF model and the Euler two-fluid model,the FLUENT is used to perform three-dimensional numerical simulation of the aerated water flow in the spillway.The results show that the calculated flow patterns and velocity results of the three models have relatively small differences which are basically consistent with the physical model test results.In terms of pressure calculation results,the calculation results of the entrainment model are in good agreement with the model test results,while the calculation results of the VOF model and the Euler model have large errors.For the distribution of turbulent kinetic energy,the calculation results of the Euler model and the VOF model are basically the same,but they are quite different from the calculation results of the entrainment model.For the aeration rate at the bottom of the center line of the spillway,the calculation results of the entrainment model and the VOF model are unreasonable,and the calculation results of the Euler model are in line with the actual situation.The research results can provide references for the simulation of aerated flow and project planning.