基于分离转捩模型的轴流式止回阀减阻试验研究  

Experiment on drag reduction in axial flow check valve based on separated transition model

作　　者：余建平[1] 罗骁[1] 付佳[1] 张希恒[1] 郑荣部 陈宗杰 

机构地区：[1]兰州理工大学石油化工学院,甘肃兰州730050 [2]福建省特种设备检验研究院,福建福州350008

出　　处：《排灌机械工程学报》2017年第5期410-416,共7页Journal of Drainage and Irrigation Machinery Engineering

基　　金：国家自然科学基金资助项目(51076061);国家质量监督检验检疫总局科技计划项目(2014QK035)

摘　　要：为了对轴流式止回阀门结构进行优化,采用RNG k-ε模型、转捩SST、转捩K-Kl-ω共3种模型对钝体绕流的边界层分离状态及壁面摩擦阻力进行数值计算,并与试验数据进行对比.结果表明:3种模型均能对边界层分离状况进行正确模拟,其中转捩K-Kl-ω模型计算出的旋涡形状与试验结果更为接近;传统的RNG k-ε模型不能反映转捩过程及转捩前后壁面摩擦阻力的变化,但建立在湍流度经验理论之上的转捩SST、转捩K-Kl-ω这2种模型均能计算出转捩所引起阻力变化情况,且2种模型的计算结果与试验结果一致,并将数值计算的流阻系数与实测数据进行比对,其中转捩K-Kl-ω模型计算所得到的阀门流阻系数相对误差为7%,比传统的RNG k-ε模型更为准确.在验证计算模型可靠性的基础之上,利用转捩K-Kl-ω模型对轴流式止回阀的结构进行了优化,发现光滑渐扩型流道的减阻效果最佳.Axial flow check valves have been widely used in oil and gas long distance pipelines, compressors in large ethylene equipment and large pumps. The flow resistance reduction in a check valve can play an important role in saving energy in production systems. Traditionally, check valves are designed by using inviscid potential flow theory and optimized by means of the standard turbulence model. The RNG k -ω model, transition SST model and transition K- Kl -ω model were adopted to calculate the separation of boundary layer over a blunt axisymmetric body and the skin friction drag. The calculated results were compared with the experimental data and it was shown that three models were able to simulate the condition of separation of a boundary layer correctly. The vortex shape predicted by the transition K - K1 - ω model is more close to the experimental results. The traditional RNG k -model cannot reflect the transitional process and the change in skin friction drag before and after transi- tion. The transition SST, K - K1 - to models, which are based on empirical theory of turbulent intensity both can predict the change in resistance caused from the transition, accordingly the calculated results of them are consistent with the experimental observations. The flow resistance coefficient calculated by the transition K -Kl -ω model is close to the experimental data with a 7% error, suggesting the model is more accurate than the traditional RNG k -6 model. Finally, the transition K- Kl -ω model was used to optimize the structure of an axial flow check valve. The optimized results show that a smoothly divergent channel can lead to the best effect on drag reduction.

关 键 词：轴流式止回阀 数值模拟 边界层分离 湍流模型 

分 类 号：S277.9[农业科学—农业水土工程] TK121[农业科学—农业工程]