3-D CFD numerical simulation of transient impact of slug flow on elbow
KANG Jinglan1, LIU fang1, HOU Qingzhi1, HE Junling2, LIN Lei3
1.School of Architectural Engineering, Tianjin University, Tianjin 300350, China;
2.College of Water Resources and Architectural Engineering, Northwest A & F University, Yangling 712100, China;
3.Suzhou Thermal Research Institute, Suzhou 215004, China
Abstract：In the piping system of power plants, the high upstream steam pressure accelerates the condensed water mass in the pipeline and exerts violent impact on the obstacles such as elbow, tee and valve. This could cause serious damage to the obstacles and the pipeline, and affect the safe operation of the plant. Considering the high-dimensional characteristics of the liquid slug motion, in this paper, 3D CFD model is developed and applied to simulate the motion and impact processes of the liquid slug, and the simulations are compared with the experimental results in the literature. It is shown that both the time history curves and the peaks of the impact pressure are in good agreement with physical experiments. At the same time, based on theoretical analysis, three pressure trends are proposed and discussed during the impact process and their results are verified by numerical simulations. By analyzing the time history of the slug length, a mass loss rate curve is obtained. Moreover, based on the obtained instantaneous slug impact velocity, a simplified method for calculation of the impact pressure is verified. It is found that the theoretical calculations are in good agreement with both the experimental and numerical solutions. These results indicate that the CFD model and the proposed calculation method for the peak pressure are reliable tools for predicting the motion of the liquid slug in the pipeline and its impact on the elbow, both of which have the prospect in practical applications.
Key words: Slug flow; Elbow impact; 3D CFD numerical simulation; Gas-liquid two phase flow; VOF
康竞澜1，刘昉1，侯庆志1，何军龄2，林磊3. 段塞流对弯管瞬态冲击的三维CFD数值模拟研究[J]. 振动与冲击, 2022, 41(23): 322-329.
KANG Jinglan1, LIU fang1, HOU Qingzhi1, HE Junling2, LIN Lei3. 3-D CFD numerical simulation of transient impact of slug flow on elbow. JOURNAL OF VIBRATION AND SHOCK, 2022, 41(23): 322-329.
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