基于混合-浓度模型的泄洪洞内水流掺气数值模拟研究  

Numerical simulation on the aerated water in a spillway tunnel based on a mixing-concentration model

作　　者：练继建[1,2] 任盼红 刘东明 何军龄 LIAN Jijian;REN Panhong;LIU Dongming;HE Junling(State Key Laboratory of Hydraulic Engineering Simulation and Safety,Tianjin University,Tianjin 300350,China;School of Civil Engineering,Tianjin University,Tianjin 300350,China)

机构地区：[1]天津大学水利工程仿真与安全国家重点实验室,天津300350 [2]天津大学建筑工程学院,天津300350

出　　处：《水资源与水工程学报》2022年第1期93-100,116,共9页Journal of Water Resources and Water Engineering

基　　金：国家自然科学基金重点联合基金项目(U1765202);河北省自然科学基金创新研究群体项目(E2020402074)。

摘　　要：掺气可以减免泄水建筑物发生空蚀破坏,对水利工程的安全运行至关重要。数值模拟方法具有低成本、无模型缩尺效应和可获得较全面的流场信息等优点,是目前研究掺气问题的有效方法。基于自主开发的NEWTANK数值模型,构建了混合-浓度数值模型用于研究掺气水流,通过对洞内掺气水流进行数值模拟研究发现,计算所得水流流速和掺气浓度与试验数据吻合良好,从而验证了该数值模型研究洞内掺气问题的可行性,此外还发现洞内形成了一个大的气流循环,上方逆向气流速度沿水流方向由2 m/s增大至5 m/s。研究表明:当闸门开度一定,来流水头由5 m增大至15 m时,水体掺气程度进一步加强,造成出口位置近底掺气浓度由0.006增大至0.060,掺气层厚度由0.08 m增大至0.12 m。Water aeration can reduce the cavitation damage of the drainage structure,which is essential to the safe operation of the hydraulic engineering.Numerical simulation has the advantages of low cost and no scaling effect,and it can produce more comprehensive flow field information,so it has become an effective method for studying aerated flow at present.Based on the self-developed NEWTANK numerical model,a mixing-concentration numerical model was developed to study the aerated water flow in a tunnel.The simulation results show that the simulated flow velocity and the air concentration are in good agreement with the experimental data,which verifies the feasibility of this numerical model.Furthermore,a large air circulation was formed in the tunnel and the reverse air velocity increased from 2 m/s to 5 m/s along the water flow direction.Further results show that when the gate opening was constant and the approaching water head gradually increased from 5 m to 15 m,the aeration of the water was further strengthened,resulting in greater bottom air concentration and aeration thickness at the outlet,which increased from 0.006 to 0.060,0.08 m to 0.12 m,respectively.

关 键 词：混合-浓度模型 混合模型 浓度模型 掺气浓度 水流流速 来流水头 泄洪洞 

分 类 号：TV131.34[水利工程—水力学及河流动力学]