中国炼油与石油化工 ›› 2013, Vol. 15 ›› Issue (3): 70-78.

• Simulation and Optimization • 上一篇    下一篇

孔口型液体分布器孔口流动的CFD模拟

于洪锋1,李鑫钢2,3,隋红3,4,李洪1   

  1. 1. 天津大学精馏技术国家工程研究中心
    2. 天津大学化工学院
    3.
    4. School of Chemical Engineering and Technology, Tianjin University
  • 收稿日期:2013-01-28 修回日期:2013-04-24 出版日期:2013-09-30 发布日期:2013-09-30
  • 通讯作者: 李洪 E-mail:lihongtju@tju.edu.cn
  • 基金资助:
    国家973重点基础研究发展计划

CFD Simulation of Orifice Flow of Orifice-type Liquid Distributor

Yu Hongfeng1,Xingang LI1,1,Hong SUI1,2,Hong LI1   

  1. 1.
    2. School of Chemical Engineering and Technology, Tianjin University
  • Received:2013-01-28 Revised:2013-04-24 Online:2013-09-30 Published:2013-09-30
  • Contact: Hong LI E-mail:lihongtju@tju.edu.cn
  • Supported by:
    the National Basic Research Program of China

摘要: 建立了一个适合的CFD模型来计算孔口型液体分布器中液位高度对孔口流量系数的影响。本文选择了SST湍流模型和GTT转捩模型来模拟不同孔口直径和液位高度下的孔口流动。在ANSYS CFX软件中,这两种模型都使用自动壁面处理方法,该方法可以根据近壁网格数在壁面函数(WF)和低湍流雷诺数近壁函数(LTRW)之间进行切换。与SST湍流模型和GTT转捩模型结合WF的模拟结果相比,这两种模型结合LTRW的模拟结果更接近实验结果,因此LTRW更适合于孔口出流边界层特性的预测。模拟结果表明孔口流动的流动状态随着液位高度的变化而变化。对于孔口流动的湍流状态,推荐SST湍流模型结合LTRW来模拟;而对于孔口流动的过渡流状态,GTT转捩模型结合LTRW优于其它的模型。

关键词: 流量系数, 孔口型液体分布器, CFD, 液位高度

Abstract: In this study, a suitable CFD (computational fluid dynamics) model has been developed to investigate the influence of liquid height on the discharge coefficient of the orifice-type liquid distributors. The orifice flow in different diameters and liquid heights has been realized using the shear stress transport (SST) turbulence model and the Gamma Theta transition (GTT) model. In the ANSYS CFX software, two models are used in conjunction with an automatic wall treatment which allows for a smooth shift from a wall function (WF) to a low turbulent-Re near wall formulation (LTRW). The results of the model simulation coupled with LTRW are closer to the experimental results compared with the models with WF, indicating that LTRW is more appropriate for the prediction of boundary layer characteristics of orifice flow. Simulation results show that the flow conditions of orifices change with the variation of liquid height. With respect to the turbulence in orifice, the SST model coupled with LTR is recommended. However, with respect to the transition to turbulence in orifice with an increase in liquid height, the predictions of GTT model coupled with LTRW are superior to those obtained using other models.

Key words: discharge coefficient, orifice-type liquid distributors, CFD, liquid height