Multiple-relaxation-time lattice Boltzmann model for binary mixtures of nonideal fluids based on the Enskog kinetic theory

在这份报纸，有 multiple-relaxation-time ( MRT )的一个格子 Boltzmann 方程( LBE )模型碰撞操作员为等温的非理想的混合物基于 Enskog 理论被开发，它是以前的单个松驰时间( SRT )的延期 LBE 模型(在 Phys 的郭和赵加快 E 68:035302 ， 2003 )。现在的 MRT-LBE 模型克服象固定 Schmidt 数字和有限粘性比率那样的原来的 SRT-LBE 模型的一些固有的缺点。广泛地使用的掸人陈(SC ) 模型，基于伪潜力概念启发式地被构造，能也被认为是现在的模型的一种特殊情况，这有趣地也被显示出，并且因此把一个稳固的基础放为这个接受得好的多相的 LBE 模型。包括静态的微滴和分层的合作水流流动，一系列数字模拟被进行与不同 Schmidt 数字和大粘性比率为不能混合的液体测试现在的模型的适用性，它可能对原来的 SRT-LBE 模型和 SC 模型困难。

In this paper, a lattice Boltzmann equation （LBE） model with multiple-relaxation-time （MRT） colli- sion operator is developed based on the Enskog theory for isothermal nonideal mixtures, which is an extension of the previous single relaxation time （SRT） LBE model （Guo and Zhao in Phys Rev E 68：035302, 2003）. The present MRT-LBE model overcomes some inherent defects of the original SRT-LBE model such as the fixed Schmidt num- ber and limited viscosity ratio. It is also interestingly shown that the widely used Shan-Chen （SC） model, which is constructed heuristically based on the pseudo-potential concept, can also be regarded as a special case of the present model, and thus putting a solid foundation for this well-accepted multiphase LBE model. A series of nu- merical simulations, including the static droplet and lay- ered co-current flow, are conducted to test the applicability of the present model for immiscible fluids with different Schmidt numbers and large viscosity ratio, which may be difficult for the original SRT-LBE model and the SC model.