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摘要建立基于Lagrange-Euler方法的多液滴运动模型,数值模拟汽水分离器的分离效率和内部液滴湿度分布。根据多液滴运动特点,选取数目密度函数描述其运动行为。通过分析液滴和流场之间的作用机理,采用δ函数构建液滴运动参数等Lagrange变量和流场参数等Euler变量的联系,从而建立多液滴运动的物理模型,并给出该物理模型的数学描述及数值求解方法。利用该模型计算得到的分离器效率与实验值及商用软件模拟值符合良好,且通过对速度场的分析,认为计算所得的分离器内部湿度分布合理。结果表明: 多液滴运动模型所得结果可靠,该模型的提出为设计和优化分离器的结构提供了强有力的工具。
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关键词 :液滴,Lagrange-Euler方法,数目密度函数,数值模拟,分离器 |
Abstract:The movement of polydispersed droplets was simulated using a Lagrangian-Eulerian model to calculate the separation efficiency and the moisture distributions in separators. A number density function was used to describe the motion. The mechanism describing the interaction between the droplets and the flow was developed with a δ-function that related the droplet and flow field parameters in a physical model of the polydispersed droplet motion. The mathematical description and numerical methods for solving the physical model was introduced. The efficiencies of the separators computed from this model fit well with experimental data and commercial CFD software model. The moisture distributions inside the separators predicted by the model are reasonable relative to the velocity fields. Thus, the results from the polydispersed droplet motion model are reliable and can be used to design and optimize separator designs.
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Key words:dropletLagrangian-Eulerian methodnumber density functionnumerical modelingseparators |
收稿日期: 2014-03-12 出版日期: 2015-05-15 |
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