旋流消能工内空腔旋流的数值模拟  

Numerical Simulation of Cavity Gyrating Flow in Gyrating Discharge Tunnel

作　　者：南军虎[1] 牛争鸣[2] 张东[1] 洪镝[3] 

机构地区：[1]兰州理工大学能源与动力工程学院,甘肃兰州730050 [2]西安理工大学水利水电学院,陕西西安710048 [3]黄河上游水电开发有限责任公司,青海西宁810209

出　　处：《四川大学学报（工程科学版）》2015年第1期76-83,共8页Journal of Sichuan University (Engineering Science Edition)

基　　金：国家自然科学基金资助项目(51166008);甘肃省青年科技基金资助项目(1310RJYA005)

摘　　要：为了克服试验研究的局限,揭示旋流消能工内部的流动特性,以公伯峡水平旋流泄洪洞为例,在原、模型试验研究的基础上,采用Realizable k-ε湍流模型对空腔旋流进行数值模拟。模拟结果表明,压强等值线沿径向大致以旋流空腔为中心的同心圆轴对称分布;旋流区和空腔内流速具有明显的分区特性,旋流区动能沿程由切向动能向轴向动能转变,并得到旋流角的印证;旋流空腔沿旋流洞轴向和径向均有变化;湍动能与湍动能耗散率的径向分布体现出水气交界面处水气混掺紊动、离心力引起壁面摩擦力的增加是空腔旋流具有较大消能率的原因。通过数值模拟与原、模型水力特性的对比分析可知,数值模拟能够客观地反映出空腔旋流内部的流场特性,成果可为旋流消能工内空腔旋流的研究应用提供参考。In order to overcome the limitation of test study and reveal the inner field of gyrating discharge tunnel,the cavity gyrating flow of Gongboxia horizontal gyrating discharge tunnel was simulated using Realizable k- ε turbulence model based on prototype and experiment tests. The simulation results indicated that the contours of radial pressure were some concentric circles with the cavity as the center approximately and presented axial symmetrical distribution. The velocity in gyrating area and cavity area had an obvious character of zoning. Kinetic energy of gyrating area changed from the tangential momentum into the axial kinetic energy along the gyrating discharge tunnel,and the same results can be obtained from the variation of rotation angle. The cavity varied greatly with the axial and radial position in the gyrating discharge tunnel. The radial profiles of turbulent kinetic energy and turbulent dissipation rate indicated that the cavity gyrating flow remarkably enhances the efficiency of energy dissipation due to the strong turbulent water in the interface between water and air and the wall friction caused by centrifugal force. The results showed that the simulation can describe the inner field of the cavity gyrating flow objectively through comparison of hydraulic characteristics obtained by simulating and testing,and provides a reference for the application of the cavity gyrating flow in gyrating discharge tunnel.

关 键 词：空腔旋流 数值模拟 水力特性 

分 类 号：TV135.2[水利工程—水力学及河流动力学]