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arXiv physics/0503160physics.flu-dynphysics.comp-ph
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轴对称多相流的格子Boltzmann模型

Lattice Boltzmann Model for Axisymmetric Multiphase Flows

Kannan N. Premnath, John Abraham

摘要:

本文提出了一种适用于轴对称多相流的格子Boltzmann(LB)模型。在二维标准格子Boltzmann方程(LBE)中加入源项,使涌现动力学转化到轴对称柱坐标系中。源项是时间和空间依赖性的,并且表示流体相的序参量以及惯性力、粘性力和表面张力力的轴对称贡献。得到了一个有效的显式二阶模型。这是通过考虑离散晶格效应的Chapman-Enskog多尺度分析,使多相流的宏观轴对称质量和动量方程恢复自洽。该模型被扩展到包括减少压缩性的影响。本文研究了粘性液体圆柱形射流通过Rayleigh毛细不稳定性和液滴碰撞形成轴对称平衡液滴的过程以及液滴的振荡、破碎和卫星液滴的形成。计算结果与现有数据的比较表明,令人满意的协议。

英文摘要:

In this paper, a lattice Boltzmann (LB) model is presented for axisymmetric multiphase flows. Source terms are added to a two-dimensional standard lattice Boltzmann equation (LBE) for multiphase flows such that the emergent dynamics can be transformed into the axisymmetric cylindrical coordinate system. The source terms are temporally and spatially dependent and represent the axisymmetric contribution of the order parameter of fluid phases and inertial, viscous and surface tension forces. A model which is effectively explicit and second order is obtained. This is achieved by taking into account the discrete lattice effects in the Chapman-Enskog multiscale analysis, so that the macroscopic axisymmetric mass and momentum equations for multiphase flows are recovered self-consistently. The model is extended to incorporate reduced compressibility effects. Axisymmetric equilibrium drop formation and oscillations, breakup and formation of satellite droplets from viscous liquid cylindrical jets through Rayleigh capillary instability and drop collisions are presented. Comparisons of the computed results with available data show satisfactory agreement.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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