旋流器后置型超音速分离管流场分析

Flow Behavior Analysis of the Cyclone Back-placed Supersonic Separator

结合气体动力学和流体热力学原理,设计了一种旋流后置型超音速分离管.针对新结构建立了三维数值计算模型,并结合可实现k-ε湍流模型对超音速分离管内部流场进行模拟,得出了管内轴心上的压力、温度、马赫数及湍动能的分布,同时对不同截面上径向的压力、温度、马赫数及旋流加速度进行了分析.结果表明:当压损比为47.5%时,分离管内Laval渐扩段(距离分离管入口98 mm处)出现明显的激波现象,获得最大马赫数1.736,此时膨胀得到的最低温度为190.52 K,可为超音速分离管提供足够的凝结动力;旋流发生器后面可获得较大的旋流加速度,产生较强的分离效果.

A type of supersonic separation structure is designed according to natural gas field condition and gas well drilling technology parameters. Based on the new device, a reasonable three-dimensional CFD model is established, and the realizable k-e turbulence model is selected to simulate the internal flow field of the supersonic separator. The separation parameters such as pressure, temperature, Mach number, and turbulence kinetic energy along the axis inside the supersonic separator are investigated, the flow characteristics along the radial direction in different sections are also discussed. The simulation results show that when the pressure loss ratio is 47.5% , the shock wave will occur in divergent of the Laval nozzle （ about 98 mm from the entrance of the supersonic separator）. Due to the expansion effect of the Laval nozzle, the lowest temperature will achieve 190.52 K. The calculation result agrees well with the previous experimental result. The new separator structure can also produce strong swirling intensity. Besides the calculation method gives a good guidance for the optimal design of the supersonic separator dimensions.